We must study hard, because we shouldn’t _______ our parents _______ .

It is not uncommon for thereproblems of communication between the old and the young.

These days, Grade 9 students stay up too late to finish ______homework and prepare for exams, as a result, some of them feel _________ the next day.

There was nothing they could do______.

Why is Mr . Yang still in the teachers’office ?—- Maybe he _______ his work yet .