When, As


What is the difference between when and as? thanks

grammar when as asked Oct 10 '13 at 16:01 Fany New member

1 answer


"We can use when and while to introduce a longer background action or situation, which is/was going on when something else happens/happened. Note that we usually use a continuous tense for the longer background action or situation.

When- and while-clauses can go at the beginning or end of sentences.

I was having a bath when the telephone rang. OR When the telephone rang I was having a bath.
While they were having a nap, somebody broke into the house.
I was working on that report when Sam called.
She was waiting for a bus when the accident occurred.
Cathy broke her arm while she was playing in the garden.
When can mean ‘at the same time as something else’.

I always wear gloves when I wash clothes.
She always takes her cellphone when she goes out.
When is used to refer to ages and periods of life. As and while are not possible in this.

His parents died when he was ten.
I was eighteen when I got my driving license.



To talk about two short actions or situations that happen/happened at the same time, we usually use as. When is also possible.

As I opened my eyes, I saw a strange sight. OR When I opened my eyes, I saw a strange sight.
As can also be used to talk about two situations that develop together. We normally use simple tenses.

As I get older, I get more optimistic. As he came into the room, all rose to their feet. As can be used to introduce a longer background action or situation."

link comment answered Oct 17 '13 at 11:01 Sanjay Expert

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