Who = Used in the subject position in a sentence, so it’s the doer of an action

Whom = Used in the object position when who is not the subject of its own clause

Who and whom are also used as relative pronouns; used to link one clause to another

The man who beat Jack in the race has been shortlisted for the competition.
The man whom you beat in the race has been out of the competition.
The man whom you met at the park yesterday is coming to dinner.
Whom should we vote for in the coming elections? [Here whom is the object of vote for]

Formerly, when we needed the objective form of who, the use of whom was considered correct. However, in modern English, the objective form who is also considered Standard English. Even in formal writing, who is commonly used. Now, you can say that whom is probably going to be obsolete and outdated:

There were several contestants in the show who the organisers had turned away before.
Who should we vote for in the coming elections?
Who would you like to speak to?                        [Spoken English]

Be careful! Do not use who straight after a preposition – the preposition is usually moved at the end: The reporter (who) the Prime Minister gave interview to.

However, in formal writing, whom is more desirable: The reporter to whom the Prime Minister gave interview.

There are other types of sentences in which we don’t use who:

The contestants, many of who were already selected, were asked to go home and prepare for the final show.                 ✗
The protestors, many of whom had severe injuries, were taken into custody. [Here whom cannot be replaced by who]    √
To whom would you like to speak? [Here whom follows the preposition to]

In formal style, a preposition before whom is preferred to leaving it ‘hanging’ at the end of the sentence:
It would be a good idea, if you could, to do some reference check about the people for whom you are going to work.            [Formal]
It would be a good idea, if you could, to do some reference check about the people whom you are going to work for.                 [Informal]

Whom is advisable if you are writing anything formal especially in constructions with a preposition. However, whom is not correct here:
He is divorcing the woman whom he alleges had run off with another man.             ✗
He is divorcing the woman who he alleges had run off with another man.               √

Who in the above example is correct since the reporting verb allege has been inserted between the grammatical subject [woman] and the verb it governs [had run away]. If you remove he alleges, you will find the sentence wrong, because whom is wrongly used as the subject.

In short, whom is rarely used in informal language.

Whom do you believe had eaten up all the biscuits before the guests came?          ✗

Who do you believe had eaten up all the biscuits before the guests came?             √  [who is the subject of had eaten not the object of believe.]

With whom did you go to the movies?  is correct but sounds like a teacher asking a student.
Who did you go to the movies with?  is technically wrong but is the way we generally speak.

Here is the simple trick to make sure which one is correct – who or whom; replace he with him and vice versa. If he sounds better, who is right; if him sounds okay, whom is correct. That’s just for the reason that pronoun whom is used to represent the object of either a verb or a preposition:

He is the man whom we contacted to drive the kids to school. (We contacted him.)
He is the man who can drive the kids to school. (He can drive the kids to school.)

In the above two examples, the he/him formula works well.

When we use but as except, we use object pronouns after but (you, her, me, us, etc.) even in subject position: No one but her had well prepared for the dance.

In formal situations, we can use subject pronouns after but:

Everyone but he knew how the events were going to unfold and the issues were starting to emerge.

Now, using ‘except’ for ‘but’ in resolving ‘she’ or ‘her’ following ‘no one but’ pattern clears this anomaly well:

All the prisoners except Timothy started to complain about the poor quality of food. (The statement does not include Timothy).

 No one but I saw the movie.

No one but me saw the movie.

Primarily, both versions are acceptable and most grammarians are of the view that but is both a preposition and a conjunction. However, remember that conjunctive but followed by a nominative pronoun seems rather literary than the preposition. It may be only stylistic choice where the use of nominative ‘he’ version might be considered to be rather formal in style. So, it is up to you which way you use it.

Everybody but him has failed the exam.

Everyone but he avoided speaking to the media about the current economic situation in the country.

All the candidates but she are the best candidate for the job.

All the candidates but her are the best candidate for the job. (except for her, excepting her).

All but one

Of 20 aspirant dancers, all but one worked very hard to achieve professional status.

(but means except meaning 19 aspirant dancers worked very hard…).

The adverbial phrase all but (without hyphenation) also means nearly, almost, or on the verge of: His paintings are all but vivid in their detail and accuracy.

All but indicates that the following action is almost complete but not absolutely. If we say:

He all but has finished the dinner. (= means there is a small amount of food left to eat).

All but can also mean all except: I have written all but the conclusion of the essay.

She waved me back once and all but disappeared into the crowd.

After several hours of deliberations, labour union and the owners all but reached a compromise.

If I were you = Refers to a hypothetical situation in the present or the future (subjunctive) and doesn’t refer to the past; it is a condition which is contrary to the fact, that is, I am NOT you:

If I were you, I would call the police.

Notice that the subjunctive ‘If I were you’ is currently going to be out of favour in modern English and has become obsolete for most people. So, by its very nature, it doesn’t have to be conjugated, and can go only in the following form: If I were you, I would call the police.

Now see this: If I were you, I would have called the police. (This construction is not in accordance with the Standard English). If I were … only indicates an imaginary or unreal situation.

Remember, ‘if I were you’ is also used when we give someone advice: If I were you, I’d probably call the police. (I think I’d call the police if I were you).

If I had been you = (also Had I been you) refers to a hypothetical situation in the present or the future (subjunctive); used when it’s irreversible: If I had been you (at some time in the past), I would have felt the same way. But, I wasn’t you, so, didn’t feel the same way:

If I had been you, I would have called the police. However, this construction (the subjunctive) is also going to become obsolete in modern English and can go on like:

If I were you, I would have called the police.

Also, see these:

If I had the money, I would have bought those shirts in the sale. (= as I am strapped for cash as ever, I couldn’t buy those shirts)

If I’d had the money, I would have bought those shirts in the sale. (= though I am well off, I didn’t have money with me at that time)

If I weren’t married, I would have proposed to Sarah. (= since I’m married, I didn’t propose)

If I hadn’t been married, I would have proposed to Sarah. (= since I was still married at that particular time (could be separated now), I didn’t propose)

If her parents were wiser, they wouldn’t have married her off to that guy. (= her parents are always unwise and are still the same)

If she had been wiser, she wouldn’t have married to that guy. (= she was in her teens then, couldn’t consider her welfare at that time)

As well as = means ‘and in addition’; ‘and also’; ‘too’; used when we want to refer another item connected with the subject we are talking about; as well as is the conjunction which is frequently misused in most academic texts. Two major errors are generally made in its use:

i) It is often used to mean and which it is not.

ii) The form of the verb following as well as; the verb must agree with the noun preceding as well as; So, when as well as is part of the subject, the verb has to agree with the noun before as well as:

Patterson, as well as Fred, want to stand for County Council election to serve the people of Essex. ✗

Patterson, as well as Fred, wants to stand for County Council election to serve the people of Essex. √ (as well as does not make subjects plural)
Drinking coffee is stressbuster as well as it increases your energy level.  ✗
Drinking coffee is stressbuster as well as increasing your energy level.     √  (verbs after as well as come in –ing form)

Sophia sings as well as choreographs.                       ✗
Sophia sings as well as choreographing.                    √         (she not only sings, but also choreographs)

OR

Sophia sings as well as she choreographs.      √       (her singing is as good as her choreographing)
He has to take the dog for a walk as well as clean the poop.   √  (after an infinitive in the main clause, an infinitive without to is used)

Notice that the phrase ‘as well as’ is not equivalent to ‘and’ because ‘and’ connects two components of equal importance while as well as focuses more on one of the elements. As well as may be termed as similar to the correlative ‘not only…but also’, however, the emphasis is put on the component that comes before as well as.
They have spoken to Bob as well as Jim.      (there is more emphasis on Bob)
On the New Year’s Eve, she likes singing as well as dancing.  (emphasis is on singing)

Now compare:
My bike and the car have broken down today.
My bike, as well as, the car has broken down today. (= not only the car but also the bike; emphasis on the bike)
In the first sentence, no distinction has been made between the bike and the car and both are on an equal footing. In the second sentence, an uneven emphasis is put on the bike, suggesting that there is stronger emphasis on the bike than it relates to the car.

Now see the sentence:
Judaism is practised in Israel, as well as in other parts of the world. ✗ (means Judaism is practised not only in other parts of the world, but also in Israel – weird). Hence, it is wrong to replace and with as well as just to avoid a repetition of and:

The present government focuses on health care, infrastructure and development, as well as immigration.           ✗ (since all these areas are equally important and none has to be more emphasised)
He broke his wrist, as well as having bruises all over the face when skateboarding.

When as well as functions as a conjunction, there are chances of errors of subject-verb agreement:
The principal as well as the teachers were called for the meeting.   ✗
In this sentence, the phrase as well as the teachers is just parenthetical; the true subject is the principal and the verb should agree with it i.e. was.

To make it clearer, using commas around the parenthetical subjects may be recommended:
The principal, as well as the teachers, was called for the meeting.   √          (Though even without commas, it is not wrong)

When two subjects are joined with as well as, the verb agrees with the first subject. That’s the rule. And to find out the subject of a sentence, remove any phrases that begin with accompanied by, along with, including, together with, in addition to, except, or as well as.
Mercury, as well as Venus, orbit the Sun.      ✗
Here, the Mercury is the subject with which the verb must agree; as well as Venus has no value.
Mercury, as well as Venus, orbits the Sun.    √

None of = Used before the demonstratives (this, that), possessives (his, your, my) or pronouns;

None of his colleagues doubt that he is a man of the highest integrity.

A traditional rule of usage says that none must always be used as singular; however, it has been used with both singular and plural verbs by distinguished writers for a long time. When none is in the sense of ‘not any persons or things,’ the plural is more common:

The accident was so terrible that none of the occupants were found to be alive.

None of them claim the responsibility to destroy the evidence.

In formal language, we use none of with a singular verb when it is the subject of the statement. However, in informal styles, we also use plural verbs:

None of that seems to amuse the guests at dinner.              (formal)

None of his sons in particular impresses us with his knowledge      (formal)

None of these foods are known to be high in antioxidants.   (informal)

When none is used to mean ‘not one’ or ‘not any,’ it takes a singular verb:

Of all my subjects, none is more uninteresting than mathematics.

None of our plans works out well in absence of Jack.

We use none of before an uncountable noun phrase to demonstrate a negative expression about every part of something:

None of the information about Pulitzer Prize winners is available on the internet.

None of this seems to amuse the audience.

None of the sugar is left in the jar. (with an uncountable noun or a singular pronoun, use a singular form)

Be Careful! Don’t use a negative word after none of or none:

None of these candidates weren’t called for the interview.                √

None of these candidates were called for the interview.                    ✗

She hadn’t seen us for 20 years, so doesn’t recognise none of us immediately.     ✗

She hadn’t seen us for 20 years, so doesn’t recognise any of us immediately.       √

Be careful! Don’t use ‘none’ directly before nouns. Instead, use no + noun or none of + noun:

No locals in this village like to mix with tourists.                                √

None of the locals in this village like to mix with tourists.                  √

None locals in this village like to mix with tourists.                            ✗

Hence, we can conclude that none can be used as either a singular or plural; however, it largely depends on what determines its number in the sentence. We usually tend to think of none as meaning not any and will choose a plural verb:

None of the public parks throughout the city allow flying kites since the beginning of this month.

However, when none means not one or when it is with uncountable noun, we use a singular verb:

None of the food tastes good; it seems it was sitting up in the refrigerator for five years.

None of my graduating students in mathematics has/have an uphill task getting a job.

None of the students have submitted their applications so far. (here the possessive pronoun their rules out the possibility of use of the singular verb).

None of our players are as energetic and dynamic as the Baltimore Ravens. (here none is used in specific comparison with a plural noun)

Notice that when we refer to two things or people in a statement, we use neither of in place of none of:

Sarah and I went to the store and none of us bought anything.                     ✗

Sarah and I went to the store and neither of us bought anything.                  √

Both ‘in the street’ and ‘on the street’ are correct, according to the contexts. However, ‘at the street’ has somewhat different story.

I am in the street = Refers to the person being in an enclosed space surrounded by buildings, shops; in the street (in the middle of the traffic or where the traffic goes); more common in UK English;

That old woman is recovering at home after plunging into the ground after a manhole in the street collapsed. (used for a position)

Today I met Nancy in the street.

The woman in the street gave me a dirty look.

When I looked out of my window at dawn, there were few people in the street. (you are away from the street)

His pocket was picked in the street.

On my way to work, there was garbage piling up in the streets.

If the authorities don’t take any precautionary measures, there will be a bloodbath in the streets.

Now it is common sight to see young girls drunk in the streets in this city.

I am on the street = Refers to the person being located on a surface; more common in US English but in the street is also used;

Bob was riding his bicycle on/in the street. (also used for an activity)

She lives on Houston Street. (without precision)   

Mr. Wilson has an office on 1343 E. 60 Street.

Jill parked his car on the side of the street.

There are far too many street vendors in this time of the year, selling fruit and vegetables on the Blacksmith Street.

Today I met Nancy on the street that turns to North from Madison Square. (refers to a specific street)

I wanted to ask for directions but there was no one else on/in the street.

Also:

They rushed out onto the streets and told the big news to anyone that passed by.

I am at the street = Refers to the person being located at a specific point or location showing an exact position; used to say that you’ve arrived at the street;

She lives at 4580, Houston Street in New York.  (address with precision)

Pamela’s office is at 32 Canal Street in New York.

Seem + to be + adjective or Seem + adjective

Seem = Gives a certain impression or have a certain outward aspect; the impression of being true, probable, or apparent; Seem is often followed by to be + an adjective:

He seems (to be) a perfect gentleman.

He has an authoritative manner and seems (to be) arrogant.

He seems to be in a bad mood at the moment about working on Sunday.

‘Seem(s)’ and ‘seem(s) to be’ are more often than not interchangeable and the difference is very subtle. However, it depends on whether we are expressing objective facts or subjective ideas:

The theatre seems to be jam-packed. (It is definitely full of audience).

According to locals, this banyan tree seems to be one hundred years old. (we believe the locals)

He seems drunk. (I guess so.)

He seems to be drunk. (His appearance tells us so)

The kids seem comfortable at the babysitter’s.                     √

The kids seem to be comfortable at the babysitter’s.             √

(both are correct with no difference in meaning)

However, see these examples:

It was Kim.         √

It seemed Kim.  ✗  [the copular verbs like be (is, am, are, was, were), appear, seem, look, sound, smell, taste, feel, become and get can’t take a specifying PC]

It seemed to be Kim.   √

With statements beginning with ‘there seem(s)’, ‘to be’ is used.

There seems to be some mix-up at the bank and we all received the wrong statements.

There seem to be some spelling errors writing the address of the recipient on the box and it was never delivered.

Usually there is no specific difference in meaning between ‘seem to be’ and ‘seem’; however, we prefer ‘seem to be’ when we mean something that looks to be definitely true (objective facts). On the contrary, we use ‘seem’ without ‘to be’ when the statement is based on personal feeling (subjective impression):

He seems to be unhappy with the results because he was confident he would win.           √

It seems to be strange that despite his best efforts, he lost the election to the Tories.   ✗

It seems strange that despite his best efforts, he lost the election to the Tories.           √

We also use ‘seem(s) to be‘ when it’s followed by an -ing form:

He seems to be drowning as his motorboat capsizes.

With infinitives: They seem to have completed this task in time.

With like: This resort seems (like) a favourite tourist attraction for the rich and famous.

Notice that we don’t use ‘to be’ when ‘seem’ is followed by a clause with that, like, or as if/as though:

It seems (that) they will fly to Switzerland on honeymoon.

It seems like you have a bad influenza.

It seems as if this winter is never going to end.

It seems as if/as though he has no guts to say that to her face.