句型转换：1、Thousands of tourists visit the West Lake every year .(改为被动语态）
问题描述：
句型转换：1、Thousands of tourists visit the West Lake every year .(改为被动语态）
2、The language lab should always be kept clean .(改为一般疑问句）
3、We weren't allowed to enter the theater by the guard .(改为主动语态）
4、The pie plate was invented ( by accident ) （对括号内部分提问）
5、The foreign teachers are often invited to dinners ( on the weekends ).(就画线部分提问）
答
1 The West Lake is visited by thousands of people every year.
2 Should the language lab be kept clean?
3 The guard didn't allow us to enter the theater.
4 How was the pie plate invented?
5 When are the foreign teachers often invented to dinners?