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Past tense of “think”
💭 To use your mind to form ideas.
Number 9 of 175 by frequency — unavoidable in ordinary English, and the past and the participle are both thought. If you learn twenty irregular verbs, this is one of them.
Mistakes people make with “think”
Not “thinked” or “thunk”. Think does not take -ed — the past simple is thought, however regular it feels to add the ending.
Phrases you will actually hear
These are worth learning whole. A verb sticks far better inside a phrase somebody would really say than on its own in a table.
Unrecognisable base, predictable ending
Think and thought barely look related, and that is normal for this group. What holds it together is the ending: -ought or -aught, shared by think, buy, bring, catch, teach, seek and fight.
The good news is that the past and the participle are identical — thought covers both — so there is one strange word to learn rather than two. The gh is silent; it is a fossil from a sound English lost centuries ago.
- Past simple: I thought about it all day yesterday.
- Past participle: She has thought it over and agreed.
The same pattern — the -ought gang — runs through 8 verbs:
Practise it
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