21.—When shall we set about doing our work?
—________ all the group members are here.
A. Until B. Since C. Unless D. Not until
22. Taking a close look at their respective(各自的) historical contexts, purposes and principles, huge
differences can be ________ between the Belt and Road Initiative(一带一路倡议) and the Marshall Plan(马歇尔计划).
A. condemned B.identified C. abused D. twisted
