These tax laws which are intended for domestic companies do not _____ to foreign companies.

When you keep your promise, no matter how much effort (努力) it takes, you will be       .

---Jack can't concentrate on his study recently． --- Yes, that might ____ why he did so badly in the last test．

—Why does Jane look unhappy today?.— A letter from her brother _________ a wave of homesickness.

It was not rare(稀少) in      that people in      fifties were going to school for further study.