With the nuclear crisis worsening in Iran, the world's attention is fixed again on is called the Middle East.
_______ the teacher’s instruction in the lab_____ important.
E-mail, as well as telephones, ______ an important part in daily communication.
Professor Wang has written some short stories, but he is______ known for his plays.
The boy promised______ in the exam any more.
-----You don’t look______. Are you ill? -----No, I’m just_______ tired.