sometimes后面加什么形态

I like to be on my own sometimes.

有时候我喜欢一个人待着。

It is sometimes possible to arrest or reverse the disease.

有时可以阻止病情发展或使病情彻底好转。

Teachers sometimes presuppose a fairly high level of knowledge by the students.

教师有时候假定学生的知识水平相当高。

Sometimes you feel better for a good weep.

有时候你痛痛快快哭上一场就会觉得好受些。

Sometimes I go by car.

有时我坐车去。