有人用了我的自行车，但我不知道是谁。

Someone has used my bike, but I don't know who (has used it).

youdao

一定有人用了我的钢笔。

Somebody must have been using my pen.

youdao

如果有人用了不洁的水冲泡，他们必须自行负责，错不在我们。

Then, if someone uses dirty water, they shoulder the responsibility, not us.

youdao

如果有人用了不洁的水冲泡，他们必须自行负责，错不在我们。

Then, if someone uses dirty water, they shoulder the responsibility, not us.

youdao