| 21. | a vacuum cleaner complete with all accessories |
| 备有配套附件的真空吸尘器
|
| 22. | a vacuum tube detector |
| 电子管检波器
|
| 23. | a vacuum tube |
| (美）真空管，电子管
|
| 24. | break a vacuum |
| 打破真空（状态）
|
| 25. | feel a vacuum in the lower regions |
| （谑）感到饥饿
|
| 26. | produce [cause, create] a vacuum |
| 产生真空
|
| 27. | coarse [low, rough] vacuum |
| 低真空
|
| 28. | extreme high vacuum |
| 极高真空
|
| 29. | fine [high, perfect] vacuum |
| 高真空
|
| 30. | a partial vacuum |
| 部分[局部]真空
|