____ your sister know Lucy?—No, she ____.

In his lecture, the professor referred to the belief, in contrast to all other countries, ______the elderly are wise, ______is particularly dominant in the Chinese culture．

Look! Somebody_______ the sofa.—- Well, it wasn’t me. I didn’t do it.

He must be ______ home now. [ ]

What about yesterday’s homework, Amy?— I found ____ hard to finish all the exercises.