Commonly Confused Words

That vs. Which

1 min read

Confused about when to use that or which? You’re not alone — this is one of the trickiest grammar points, even for native speakers!

That

That is used to give essential information — information that is necessary to understand the sentence. There are no commas around it.

The car that she drives is electric. (Not just any car — the one she drives.)
Books that teach clearly are my favorite.
This is the app that I use every day.

Use that when the information tells you *which one* or *which kind* specifically.

Which

Which is used to add extra (non-essential) information. The sentence would still make sense without it. It's usually set off by commas.

Her car, which she bought last year, is electric. (Extra detail — not essential.)
My laptop, which is five years old, still works great. 💻
The movie, which was based on a true story, won several awards.

Use which when the detail is interesting but not necessary to identify the thing you’re talking about.

💡 Tip

If the information is essential → use that (no commas).
If it’s just extra info → use which (with commas).

Test your knowledge 📝

Question 1 sur 8Score: 0/8

The phone ___ I bought last year still works perfectly.

Discover the app: Shaky English

Join 100,000 people who are improving their English skills on the Shaky English app

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Commonly Confused Words

That vs. Which

1 min read

Confused about when to use that or which? You’re not alone — this is one of the trickiest grammar points, even for native speakers!

That

That is used to give essential information — information that is necessary to understand the sentence. There are no commas around it.

The car that she drives is electric. (Not just any car — the one she drives.)
Books that teach clearly are my favorite.
This is the app that I use every day.

Use that when the information tells you *which one* or *which kind* specifically.

Which

Which is used to add extra (non-essential) information. The sentence would still make sense without it. It's usually set off by commas.

Her car, which she bought last year, is electric. (Extra detail — not essential.)
My laptop, which is five years old, still works great. 💻
The movie, which was based on a true story, won several awards.

Use which when the detail is interesting but not necessary to identify the thing you’re talking about.

💡 Tip

If the information is essential → use that (no commas).
If it’s just extra info → use which (with commas).

Test your knowledge 📝

Question 1 sur 8Score: 0/8

The phone ___ I bought last year still works perfectly.

Discover the app: Shaky English

Join 100,000 people who are improving their English skills on the Shaky English app

Other similar rules

Vocabulary

Em Dash vs. En Dash vs. Hyphen

Vocabulary

Commas

Common confusions

Less vs. Fewer

Common mistakes

Modal Verbs for Advice (should, ought to, had better)

Common mistakes

Participle Clauses (-ing / -ed / perfect clauses)

Agreement rules

Parallel Structure (Parallelism)

Common confusions

Who vs. That

Common confusions