CWClearWord Lab

Confusing Words

Since vs For

Since is for a starting point; for is for a duration.

Quick Answer

Use 'since' with a specific point in time (e.g., Monday, 2020). Use 'for' with a period of time (e.g., two hours, five years).

Core Difference

Since indicates the start of a period; for indicates the length of a period.

Simple Explanation

Since and for are used to talk about time, especially with perfect tenses. 'Since' tells us when something started. It is followed by a specific time or event, like 'since 2010' or 'since I was a child'. 'For' tells us how long something lasts. It is followed by a duration, like 'for three years' or 'for a long time'.

Word Details

since

preposition

from a specific time in the past until now

since + point in timesince + clause

for

preposition

indicating a period of time

for + duration

Examples

since

I have lived here since 2015.

Starting point.

since

She has been sleeping since 10 p.m.

Specific time.

for

I have lived here for eight years.

Duration.

for

He studied for three hours.

Length of time.

since

We have known each other since we were kids.

Starting event.

for

They have been married for 20 years.

Duration.

Practice Quiz

Choose one answer. Mistakes are saved for review.

1. I have known her ___ 2018.

2. He has been a teacher ___ ten years.

3. They have been married ___ last June.

4. We waited ___ an hour.

5. I haven't eaten ___ breakfast.

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