building blocksPrepositions of Time — for, during, while


For, During, and While are three of the most common prepositions used in time expressions.

Here are the general rules of using for, during, and while.


Explanation Examples
For is used to express how long something or someone has been doing something.

For is used to state a period of time and is usually used with a noun or a pronoun.
We waited for an hour outside the theatre for you.

Curtis has been riding his bicycle for two hours.

Rosie, my dog, has been barking for a long time.

The traffic has been bad for the last five years.


Formula: (while + subject + verb)

Explanation Examples
While is used to represent the length of time an action has been happening. While I was playing the piano, my husband was doing the dishes.
While is used when speaking about two actions happening at the same time. The length of the action is not important. While we were eating dinner, the radio was playing.
While is used with a subject and a verb (while + subject + verb) The doorbell rang while we were eating dinner.


Formula: during + noun (pronoun)

Explanation Examples
During is used to say when something happens.
I will be really busy during the next year.
During is used with a noun/pronoun. The children were sleeping during the movie.
The power went out during the snow storm.

When you are sure that you understand the lesson, you can continue with the exercises.