Home → Irregular verbs → understand

Past tense of “understand”

💡 To know what something means.

Number 62 of 175 by frequency — common in reading and television, less so in your own speech, and the past and the participle are both understood. Recognising it is the priority.

Mistakes people make with “understand”

Not “understanded”. Understand does not take -ed — the past simple is understood, however regular it feels to add the ending.

Only the vowel moves

The consonants stay exactly where they are and the vowel changes underneath them: understand → understood, u-e-a → u-e-oo. Nothing is added and nothing is dropped.

The past simple and the past participle are the same word, understood. Half the work disappears: learn understand · understood and you have the whole verb. What is left is telling the two jobs apart — I finally understood the joke. is the past simple, He has never understood math. is the perfect, and have does all the signalling.

This is worth hearing rather than reading. Say understand and understood one after the other — the shape of your mouth changes, the word does not.

The same pattern — twins — runs through 73 verbs: