Many a student ________ failed in the biology exam，and Tom is the only one of them who ________ decided to give up the course.
| A．have；has | B．have；have | C．has；have | D．has；has |
---We all had a lot of fun at the barbecue yesterday. Pity you weren’t there.
---I really should have gone with you, but I ________ on some remaining problems.
| A．was working | B．would work | C．worked | D．had worked |
If you want to study the nature of the universe, first of all, you must be clear about its ________.
| A．traditions | B．consequences | C．signs | D．origins |
---Do you think I can pass the test?
---________, I’m afraid.
| A．You can | B．Of course | C．Not a chance | D．A little bit |
________ from endless homework on weekends, the students now find their own activities, such as taking a ride together to watch the sunrise.
| A．Freed | B．Freeing | C．To free | D．Having freed |
Few people paid full attention to their health conditions ________ they were seriously ill.
| A．when | B．if | C．until | D．after |