— Believe it or not, my sister and I are twins.
— Oh, you must have had the case _________ you were taken for your sister.
| A．which | B．whose | C．where | D．when |
Whocanthinkofasituation__________thisidiomcanbeused?
| A．which | B．that | C．where | D．inthat |
You may choose one from _________ was left.
| A．that | B．all | C．those which | D．what |
It isn't decided yet _______ we will attend the meeting.
| A．if | B．why | C．that | D．whether |
It takes time to build ______ when you are learning a difficult skill.
| A．confidence | B．strength | C．energy | D．belief |
Four-fifths of the crop ______.
| A．are ruined | B．was ruined | C．were ruined | D．have been ruined |