按要求完成句子
1. I was three years old when I started doing the things.(对画线部分提问)
_____ _____ _____ you when you started doing the things?
2. I went to the zoo last Sunday.(对画线部分提问)
What _____ _____ _____ last Sunday?
3. I saw some sharks.(改为一般疑问句)
_____ you _____ _____ sharks?
4. The students had a terrible school trip.(改为否定句)
The students _____ _____ a terrible school trip.
