[解析]
1,
They always go to school on foot,
They always go to school on foot.
2.
The mouse is afraid of the cat.
The mouse is afraid of the cat.
3,
Marry studies Chinese everyday,
Marry studies Chinese everyday.
4.
I'm going to the science museum with my father.
I'm going to the science museum with my father
5
The scientist works at a university,
The scientist works at a university.