| 1. | At any time the macrophage system might be injured by viral infection or air pollutant exposure . 巨噬细胞随时都可能受病毒感染或空气污染物所损伤。 |
| 2. | By food or water contaminated with the virus -食用或饮用受病毒污染的食物或水 |
| 3. | 1 . by food or water contaminated with the virus 1 .食用或饮用受病毒污染的食物或水 |
| 4. | 1 . by food or water contaminated with the viruses 1 .食用或饮用受病毒污染的食物或水 |
| 5. | Diseases sometimes attack plants and trees 植物和树木有时亦受病之侵害。 |
| 6. | 3 . by contact with contaminated objects ; or 3 .接触受病毒污染的物品或 |
| 7. | The plant is not susceptible to disease 这种植物不容易受病害侵袭。 |
| 8. | She ' s suffering from a condition that no one understands 她正受病痛折磨,她的病情没人能明白 |
| 9. | V . by transfusion of contaminated blood or blood products V .输入受病毒污染的血液或血液制成品。 |
| 10. | They seem vulnerable to viruses , 人类看起来易受病毒的侵害 |