1.We must (keep) the classroom(clean)(保持...干净)
2.I’m sorry to keep you(waiting)(for)(等待)me so long
3.The teacher asked me(not)(to)(hand)(in)(不要上交)my homework so late next time .
4.I hear someone(knocking)(at)(敲门)the door .
1.We must (keep) the classroom(clean)(保持...干净)
2.I’m sorry to keep you(waiting)(for)(等待)me so long
3.The teacher asked me(not)(to)(hand)(in)(不要上交)my homework so late next time .
4.I hear someone(knocking)(at)(敲门)the door .