Listen! I hear some birds ___________ the tree.A. sing in B. singing in B. sing on D. singing on
---Do you mind _________your room? ---No, I’ll do that after finishing _________this article.
There used _______ a bus station in front of the building.
He worked late ______ eleven o’clock yesterday.
---I don’t know ___________next. ----You’d better finish your homework first.
His parents live ______ in a small house, but they don’t feel ..