又【yòu】

又 before a verb says something has happened again. The repeat has already taken place, so the sentence usually ends in 了.

Said to someone, it often sounds like a complaint: this keeps happening.

又 or 再

又 is for a repeat that has happened. 再 is for one that hasn't.

• × 我明天又来 → 我明天再来

The exception is a repeat that is certain because it comes round on schedule. 又 then looks ahead, with 了 at the end.

With 没 and 不

又 goes in front of the negative: 又没 is "didn't, again", 又不 is "won't, again".

• × 他没又做作业 → 他又没做作业

The same 又 also links two descriptions in 又…又… "both … and …", which is a separate point.