--- How many students are there in each group?
--- Usually each group _______ six students in our class.
A:is made from
B:is made up of
C:is made in
D:is made of
看图填空.
____
—Do you know why the teacher asks for me?
—He wants you to _____ your absence last night.
clean close clever class cloudy clothes
我国目前对海洋资源的开发程度( )