Tony ______ his homework this morning before he went to school.
| A．has done | B．did | C．has done | D．will do |
the morning train, he would not have been late for the meeting.
| A． | Did he catch | B． | should be catch | C． | has he caught | D． | Had he caught |
I think _______ impresses me about his painting is the colours he uses.
| A．what | B．that | C．which | D．who |
The two countries are going to meet to _______ some barriers to trade between them.
| A．make up | B．use up | C．turn down | D．break down |
English is a language shared by several diverse cultures, _________ uses it differently.
| A．all of which | B．each of which | C．all of them | D．each of them |
We won’t start the work until all the preparations __________.
| A．are being made | B．will be made | C．have been made | D．had been made |