This lesson was so boring ____ some students began to sleep in class.
After a short rest , the farmers keep ______ till tonight.
Our school has several weeks _____ in the summer time.
--- What’s your plan for this weekend? --- I’m going to _____ it with my parents.
--- How many _____ teachers are there in your school? --- ____ them _____ over one hundred.
The Yellow River is _________river in China.