以动词go为例

肯定句：

I shouldgo.

You wouldgo.

He / She / It wouldgo.

We shouldgo.

You / They wouldgo.

否定句：

I should not go.

You would notgo.

He / She / It would notgo.

We should notgo.

You / Theywould not go.

例子：

David said he wouldcome back the next day. 大卫说他第二天会回家。

I thought it was goingto snow. 我原以为要下雪了。

He asked when the train was arriving. 他问火车几点钟到。