I know ______ is important to know my own limitations, but _______ is difficult is to help others to know their own limitations.
| A．it, it | B．what, what |
| C．it, what | D．what, it |
______you may have，you should gather your courage to face the challenge.
| A．However a serious problem |
| B．What a serious problem |
| C．However serious a problem |
| D．What serious a problem |
31. ---Did you receive his call last night？I was disturbed several times.
---He ______ again. That’s his typical style.
| A．should be blind drunk |
| B．may be blind drunk |
| C．must have been blind drunk |
| D．could have been blind drunk |
His mind went so blank that little ______ down for the first ten minutes in the test.
| A．he wrote | B．he will write |
| C．did he write | D．will he write |
---Why was it ______ you were so angry？
---Because we failed to take part in the basketball match.
| A．which | B．that | C．how | D．when |
The Bakers intend to buy a house but _____ must be within their power.
| A．they | B．one | C．it | D．which |