Scientists photographed for the first time ever _____ wild gorillas used a stick to test the depth of a pool before getting into it, according to a recent study.
A.which | B.what | C.that | D.when |
---- My baby has a heart trouble. ---- Did the doctor find it difficult ______ ?
A.in treating | B.treating | C.for treating | D.to treat |
---- Where did he go? ---- He went to another store ______.
A.to buy pencils | B.for buying pencils | C.buy pencils | D.buying pencils |
---- Why was the official meeting called? ---- ______ new officers.
A.Select | B.Selecting | C.To select | D.For selecting |
Because of air pollution being greatly reduced, this city is still ______.
A.a good place which to be lived in | B.lived as a good place |
C.a good place to live in | D.living in as a good place |
---- I didn't hear you come in last night. ---- That's good. We tried_____ noisy.
A.not be | B.not to be | C.to be not | D.to not be |