.Your son has kept _________ for two hours. You’d better ask him to have a rest.
#51260
A
study
B
studied
C
to study
D
studying
推荐题目
Thank you for ____ us some help.
#51241
A
give
B
giving
C
to give
D
gives
 My mother has had the clothes _______already.
#49898
A
was washed
B
was washing
C
to wash
D
washed
He thinks _____ history about Chinese is very important. 
#49013
A
studied
B
studying
C
studies
D
study