erstandings resulting from lack ofsocial communication, if not ______ properly, may lead to serious problems．

____ make progress, she has been studying hard.

When she realized I _______ her, she quickly made a pose, smiling

I can think of many cases ______ studentscan’t write a good article though having a large vocabulary.

_______ they _______ the book _______ to the library yet—Yes, they have.