to his scientific research, the professor cared little about his family.
| A．Devoting | B．Devoted | C．Having devoted | D．To devote |
34．John lost his job last year, but it wasn't long ______ he found a new position in another company．
| A．after | B．while | C．as | D．Before |
33．— You seem to be familiar with this city!
— I ______ English in a school here for two years．It's great to be back again!
| A．taught | B．have been teaching | C．had taught | D．have taught |
32．Miss Bell joined the search-and-rescue team when she was 14, the youngest age ______ one can be admitted．
| A．from which | B．at which | C．that | D．Which |
31．Laura was asked several questions, but she couldn't answer ______ of them．
| A．none | B．either | C．neither | D．Any |
30．1 tried to fix the car myself but ______ the attempt after a couple of hours．
| A．gave in | B．gave off | C．gave up | D．gave away |