As if = Used to express that something is unlikely and should not be considered
As though = The same as ‘as if’
The difference between ‘as if’ and ‘as though’ is subtle and both of them can be used interchangeably. However, ‘as if’ is more common than ‘as though’:
She acts as if she were Cleopatra.
It was as if a great weight had been lifted off my back.
He looks as if he has had his lunch.
It looks as though I’ve been here before.
He is nowhere in sight. It looks as though his car was stuck in traffic.
We can use was or were in informal English or conversation, however, in formal writing we use were:
She looked at me as if I were lying. (formal)
She looked at me as if I was/were lying. (spoken English)
If the situation is based on fact or reality, we use a real tense to show present time:
He looks as if he doesn’t like to talk about those years. (he doesn’t like to talk).
He looks as if he has the knowledge of her whereabouts. (he has the knowledge of her whereabouts)
We also use a real tense to refer past time, if the situation is true:
He seems as if he hasn’t taken a bath for days. (= he hasn’t taken a bath for days)
The Clauses beginning with as if/ as though define an unreal or improbable situation when
they are followed by an unreal tense (the past subjunctive or the past perfect subjunctive).
He looks as if he had no knowledge of her whereabouts. (he gives the impression of not
having any knowledge of her whereabouts, but (probably) has or we don’t know whether
he has or not)
He looks as if he didn’t like to talk about those days. (= he gives the impression that he (probably) doesn’t like to talk about those days or we don’t know whether he likes or not)
When the verb preceding as if/ as though is in the past and it (as if/ as though) is followed by past subjunctive, the structure will be:
He looked as if he didn’t like to talk about those days. (= whether he liked or didn’t like to talk can only be inferred from the context).
We use the past perfect subjunctive after as if/ as though to denote an unreal past situation.
He seems as if he hadn’t taken a bath for days. (= it seems that he hasn’t taken a bath for days, but he (probably) has or we are not sure of it)
If the verb before as if/ as though is in the past, the verb following the as if/ as though comes in the past perfect and the structure of the sentence will be:
He seemed as if he hadn’t taken a bath for days.
The old woman says it looks as though her troubles were over.
In the beginning, it looked as though the project would not see the light of day.
Hello! Anybody home? It looks as though everyone else has left. (perhaps everyone has left)
Grandma looked as though she was annoyed by the sound of music.
Lately he’s been bossing us around as though he were the owner of the company.
He looks as though he was running late for the office. (perhaps he was late)
She looked as if she didn’t mind my asking such a personal question. (= whether she was
bothered or not by my asking the personal question can only be inferred from the context).
He looks as if he is an expert on the subject. (= he is an expert)
He looks as if he was/were an expert on the subject. (he gives the impression that he is an expert and we are not sure of it)