九年级英语上册十二单元重要知识点总结(2)

　　3. When I got to school, I realized I had left my backpack at home. 当我到达学校时，我才意识到我把背包忘在家里了。

　　4. By the time I walked into class, the teacher had started teaching already. 当我走进教室时，老师已经开始讲课了。

　　5. By the time I arrived at the party, everyone else had already showed up. 当我到达晚会时， 其他的每个人都已经到了。

　　6. When he put the noodles into the bowl, he realized he had forgotten to add the green beans. 当他把面条放进碗里时，他意识到他忘了添加绿豆荚了。

　　7. Before she got a chance to say goodbye, he had gone into the building. 在她得到一个向他告别的机会之前，他已经进入楼房了。

　　【考点详解】

　　1. By the time I got outside, the bus had already left. 当我出来的时候，公共汽车已经走了。

　　by the time作连词引导时间状语从句，当从句用一般过去时，主句用过去完成时;当从句用一般现在时，主句用一般将来时或将来完成时。

　　如：By the time he was ten, Tom had built a chemistry lab himself. 等到了十岁的时候，汤姆自己建了一个化学实验室。

　　I’ll be in bed by the time you get home. 你到家时，我已经上床睡觉了。

　　2. When she got to school, she realized she had left her backpack at home. 当她到学校时，她意识到她把背包忘在家里了。