As and since

As and since

We often use as and since when we want to focus more on the result than the reason. Asand since are more formal than because. We usually put a comma before since after the main clause:

[result]I hope they’ve decided to come as [reason]I wanted to hear about their India trip.

[result]They’re rather expensive, since [reason]they’re quite hard to find.

We often use as and since clauses at the beginning of the sentence. We use a comma after the as- or since- clause:

Since everything can be done from home with computers and telephones, there’s no need to dress up for work any more.

As everyone already knows each other, there’s no need for introductions. We’ll get straight into the business of the meeting.

We use because, not as or since, in questions where the speaker proposes a reason:

Are you feeling unwell because you ate too much?

Not: Are you feeling unwell since you ate too much? or … as you ate too much?