Learn English – Did I misunderstood

past-tense

I'm confused about which one of these is correct:

"Did I misunderstood the question?" or "Did I misunderstand the question?"

Not sure why I feel the first one is correct and when searching the phrase I see many people write it like that too, could you help me?
Thanks

Best Answer

Auxiliary "do" always always always takes the basic form ("infinitive") of the main verb, never a past, a past participle, an '-ing' form, a third person '-s' form or anything else. Do/did/does understand.