Question

David ( not win) all his matches this year

Answer 1

David  not win all his matches this year.Перевод :

Дэвид не выиграл  все свои матчи в этом году.

Поэтому нужно вставить "Not win"

Answer 2

It seems there might be a typo in your statement. If you meant to say "David won all his matches this year," then it would mean that David was victorious in every match he participated in during the current year.

However, if you intended to say something else, please clarify, and I'd be happy to help!