PartIISectionA
21. If nothing ________, the oceans will turn into fish deserts.
A. does B. had been done C. will do D. is done
22. — I’ve prepared all kinds of food for the picnic.
—Do you mean we_____ bring anything with us?
A. can’t B. mustn’t C. shan’t D. needn't
23. All of us find ________ difficult to get along well with him.
A. this B. that C. it D. one
24. I’m afraid these are _________ I can tell you.
A. that B. what C. why D. how
25.______ cloning human embryos is not legal in many countries, some scientists are already pushing ahead with the research .
A. While B. Because C. Whether D. Unless