第 42 课: 因果和假设-2

The man can see because his eyes are open. 因为男人睁着眼睛，所以他能看见。

The man could see if his eyes were open. 如果男人睁开眼睛，他就能看见。

The man can climb up to the top of the building because he has a ladder. 因为男人有梯子， 所以他能爬到房顶。

The man could climb up to the top of the building if he had a ladder. 如果男人有梯子， 他就能爬到房顶。

The man can talk. 男人能谈话。

The man could talk if the woman didn't have her hand over his mouth. 如果女人的手没有捂着男人的嘴，他就能谈话。

She can write. 她能写字。

She could write if she had a pen. 如果她有笔，她就能写字。