she works hard _____ all her lessonsa.atb.aboutc.ofd.in

问题描述:

she works hard _____ all her lessons
a.at
b.about
c.of
d.in

A
works hard at all her lessons - 在每门课都下了功夫,很用功。

似乎是选at,因为一般work hard in dong sth/at sth

a.at

当然D