TheywentclimbingthemorningofMayIandcamebacktheafternoon．（）A.on；onB.in；inC.on；inD.in；on

Question

They went climbing         the morning of May I and came back         the afternoon．（　　）

A. on；on

B. in；in

C. on；in

D. in；on

Answer 1

答案：C．
根据设空处后面的时间"the morning of May 1"可知句子中的时间状语是具体到某一天的早晨，所以用介词on． 第二个设空处表示"在下午"用in the afternoon，故选C．