1，He asked if I didn’t come to school yesterday. 他问我昨天是不是没来学校。
2，He really doesn't know if there is anything useful in the box? 他真的不知道盒子里是否有东西吗？
3，I don’t know if he will come or not.我不知道他是不是回来。
4，Please let me know if you need help. 如果你需要帮助请告诉我。
5，I don’t know if it won't rain tomorrow..我不知道明天是不是会下雨。
6，He asked me if I was reading the story The Old Man and the Sea when he was in. 他问我他进来的时候我是否正在读<<老人与海>>。
7，The reporter asked if the government would take necessary measures to put down the to-do. 记者问政府是否会采取必要的措施镇压骚乱.
8，I don’t know if there will be a bus any more. 我不知道是否还会有公交车.
9，I will go to the cinema if it doesn't rain tomorrow. 如果明天不下雨我就去看电影。
