Question

15. The time and effort he has devoted during the past few years     trees in that remote area is now considered to be of great value.

A. to plant      B.  to planting

C. plant         D. planting

Answer 1

15.   B 4查非謂語動詞。句意：他在過去的這些年里在那個(gè)偏遠(yuǎn)的地區(qū)種樹所付出的時(shí)間和精力現(xiàn)在被認(rèn)為是很值得的。短語devote sth to sth中to是介詞，故lo之后應(yīng)為名詞或動名詞形式。此處表示把時(shí)間和精力花費(fèi)在了種樹上，所以應(yīng)為devote time and effort to planting trees。 故選B。