The illness of her son is so ______ that she cannot go to sleep at night.
| A．satisfying | B．worrying | C．surprising | D．puzzling |
_______ you work hard, you won’t solve this problem.
| A．Even | B．As | C．Unless | D．Since |
My uncle _____ in Taiwan for 20 years. Now he has settled down in mainland.
| A．lived | B．had lived | C．has lived | D．was living |
No doubt she will be late. It’s ______ of her to keep all the other guests waiting.
| A．original | B．logical | C．normal | D．typical |
The teacher was absorbed in writing something, only _____ now and then to refer to a book or another.
| A．to stop | B．stopped | C．stopping | D． having stopped |