Since VS For
Since vs. For
Understanding the Difference Between "Since" and "For"
Both since and for are used with the present perfect to talk about how long something has been happening — but they answer two different questions. Let's break it down!
For — how long a period of time is
Use for when you're talking about a duration — a length of time, no matter when it started.
• I've lived in the U.S. for three years.
• She's been studying English for six months.
• We've known each other for a long time.
Since — when the period started
Use since when you're talking about a starting point — a specific moment in time.
• I've lived in the U.S. since 2023.
• She's been studying English since January.
• We've known each other since college.
Quick Reference
| Word | Answers the question… |
|---|---|
| for | How long? (a duration: 3 years, 2 hours, a while) |
| since | Starting when? (a point in time: 2023, Monday, I moved here) |
Common Mistake
A common mix-up is using since with a duration instead of a starting point:
Try It Yourself
Fill in the blank with since or for:
1. I haven't seen her ____ last summer.
2. They've been married ____ ten years.
3. He's been waiting ____ 20 minutes.
4. We've lived in this house ____ 2018.
(Answers: since, for, for, since)
