他昨天直到完成作业才看电视 He ___ ___TV ____he finshed his homework yesterday 中间空白处应填什么?

He didn't watch TV until he finshed his homework yesterday

这是until的用法:
until前是否定句时,到它后面的时间时就开始做某事了;它前面是肯定句时,到它后面所指的时间时就不怎么了.
所以,本句就填didn't watch,until

He didn't watch TV until he finshed his homework yesterday
not ...until

didn't watch until