What is the difference between since and for?

In French, the word depuis can be used as a translation for both since and for. As a result, the difference between since and for is not always clear.  Consider the following sentences and their French translations:

I have been working since 2004. | Je travail depuis 2004.

I have been working for 5 years.  | Je travail depuis 5 ans.

In this post, we’ll do our best to explain the difference between since and for. We’ll provide some very clear examples of when to use each. Then, we’ll finish off with a quiz so that you can practice what you’ve learned!

How to use since

Since can be used in three ways:

1) as a preposition followed by a noun

I have been studying English since 2005.

I haven’t stopped working since Tuesday.

The sun has been shining since this morning.

2) as an adverb

I visited Japan in 2001 but haven’t been back since.

I gave up smoking 5 years ago and haven’t picked up a single cigarette since.

3) as a conjunction

Since you’re asking, I’m going to tell you.

Since he wanted to work on the project so badly, I assigned it to him.

I haven’t played tennis since I was in college.

How to use for

There are multiple uses of for. To get a full overview, feel free to click on this link.

In the context of time, for is used to signal a duration of time.

Examples:

I have been running for an hour.

I have been eating at that restaurant for 10 years.

I’ve been waiting for a lifetime.

She has been sick for 2 weeks.

She has been studying for the last month.

Illustration: The difference between since and for

Since is used when we want to refer to a specific point of time in the past.

Example:

I haven’t loved pizza since only yesterday. I haven’t loved pizza since only last year.

I have loved pizza since college!

And, I still love pizza today.

For, on the other hand, refers to a time period, or the space of time between one point in the past and now.

Example:

I was in college 20 years ago.

Now – 20 years = a time period of 20 years.

I have loved pizza for (a time period) of 20 years.