| 1. | The incubation period usually is 8 to 14 days . 潜伏期通常为8-14天。 |
| 2. | The period after supper was given over to games . 晚饭后是游戏时间。 |
| 3. | The school day is divided into seven periods . 每个授课日分为七节课。 |
| 4. | In the slack period mr. baker came in . 正在空闲的时候贝克先生进来了。 |
| 5. | The period of waiting was not limitless . 等待的时候不会是没有尽头的。 |
| 6. | It is a period prolific of great poets . 这是伟大诗人辈出的时代。 |
| 7. | It was a productive and fertile period . 这是一个硕果累累的时期。 |
| 8. | It was a period of substantial change . 这是一个本质变化的时期。 |
| 9. | I 've been teaching four periods this morning . 今天上午我已教了四节课。 |
| 10. | The heat period appears at regular intervals . 其发情期有一定的间隔时间。 |