Breakdown of Мы чуть было не съели червивую сыроежку.
Questions & Answers about Мы чуть было не съели червивую сыроежку.
It means almost or came very close to doing something.
So Мы чуть было не съели червивую сыроежку means that we nearly ate the mushroom, but in the end we did not.
A useful point: even though the sentence contains не, the whole expression чуть было не + past verb usually means something almost happened.
Compare:
- Мы не съели сыроежку = We did not eat the russula
- Мы чуть было не съели сыроежку = We almost ate the russula
By itself, yes, не usually negates a verb. But in the fixed pattern чуть не or чуть было не, it does not simply mean ordinary negation. The whole expression functions idiomatically as almost.
So here:
- съели = ate
- не съели = did not eat
- чуть было не съели = almost ate
This is one of those cases where you should learn the whole chunk together.