| 1. | It is proper that he should do so . 他这样做是适当的。 |
| 2. | It is proper that such a bad man be punished severely 这么坏的人受重罚是应该的。 |
| 3. | It is proper that such a bad man be punished severely 这么坏的人受重罚是应该的。 |
| 4. | It is proper that we ( should ) keep public places clean 我们保持公共场合的洁净是合适的。 |
| 5. | It is proper that we ( should ) keep the public places clean 例?我们当保持公共场所清洁是应当的。 |