题目

I will ________ more effort in my studies this term.A. put up B. put on C. put down D. put in 答案：【答案】D【解析】句意：这学期我将更加努力地学习。A. put up张贴，举起；B. put on穿上，增加，上演 ；C. put down放下，镇压；D. put in在…上花费put in more effort是“更加努力”的意思。结合句意可知，答案为D。已知函数f(x)＝若f(a)＝，则a＝(　　)A．－1B．C．－1或D．1或－