Question

i have fallen behind in my study,so i have got to___

A.make an effort B.make efforts C.study hard D.make effort 答案是D，请说明一下~~

Answer 1

答案是d
因为前俩型宽个词组是有固定用法的
make
an
effort
to
do
sth
make
efforts
to
do
sth.
而make
effort是泛指要努力了，要争气了卜返亮，
它可世或以单独用，后面不需要跟
不定式
去组句。