Before a problem can be solved, it must be obvious ______ the problem itself is.
A. what B that C which D why
Eating properly and exercising _______ make one enjoy a longer and healthier life.
| A．normally |
| B．generally |
| C．regularly |
| D．directly |
— _______ you got to know my telephone number?
— Through a friend of yours.
| A．How was it |
| B．How was it that |
| C．Was it how that |
| D．How did |
It is almost five years_________we saw each other last time.
| A．before |
| B．since |
| C．after |
| D．when |
—Do I need to give a tip if I eat at a fast food restaurant in the United States?
—Yes, it’s a common ______ to tip waiter in a restaurant.
| A．sense |
| B．custom |
| C．method |
| D．practice |
________difficulties we may come across, we’ll help one another to overcome them.
| A．Wherever | B．Whatever | C．However | D．Whenever |