下列各组代数式中，属于同类项的是

A．2x²y与2xy²

B．xy与－xy

C．2x与2xy

D．2x²与2y²

用所给词的适当形式填空（必要时可加助动词）.

小题1:__________（that）girls are Amy’s sisters．

小题2:That is __________（she）father．

小题3:What’s __________（you）last name?

小题4:These __________（picture）a他while and black．

小题5:Here __________（be）Mona’s keys．

小题6:_________ （do）she have a dictionary?

小题7:Ed．Smith__________（have）7 basketballs and 8 tennis rackets．

小题8:Let us ________ （join）the school sport club．

小题9:__________（Linda）father and mother are in the school．

小题10:________ （be）she your grandmother?