Students ____ ____ ____（应该）work hard at their lessons.

Students ____ ____ ____（应该）work hard at their lessons.
Students ____ ____ ____（应该）work hard at their lessons.

Students ____ ____ ____（应该）work hard at their lessons.
are supposed to
are expected to

are supposed to

are supposed to
这里是三个空的，应该还可以译为：should ；ought to .
希望帮到你！

很高兴为您
are supposed to
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