It is a good habit of ______ to read a few lines before going to bed.

Although you may meet some difficuIties,you should never．

Do you know when we can go back home? —Sorry, I don’t. Because of the heavy snow storm, highways have been blocked and flights have been __________.

While he_____ on the phone, a man walked into his room.

Where is my pen?—I _________ it on the desk, but I don’t know who _________ it away.