| 21. | The acceleration of tooth decay is caused by lack of care. |
| 不注意保护，牙齿会加速腐坏。
|
| 22. | have one's teeth examined for decay |
| 诊察龋齿
|
| 23. | signs of incipient tooth decay |
| 早期龋齿的征象
|
| 24. | preservation against [from] decay |
| 防腐
|
| 25. | the preservation of timber against decay |
| 木材的防腐
|
| 26. | hasten the process of decay |
| 加速腐败过程
|
| 27. | fall into decay |
| 衰败，衰微；塌坏，年久失修
|
| 28. | bacterial decay |
| 细菌性腐烂
|
| 29. | dental decay in children |
| 儿童牙齿的柱蚀状况
|
| 30. | moral decay |
| 道德败坏
|