have to是什么時態

　　例句：

　　1、We were to meet again many years later.

　　我們注定多年后會再次相遇。

　　2、They were to meet at a given time and place.

　　他們要在規定的時間和地點會晤。

　　3、If Apple were to do so, this would be another catalyst for the stock.

　　如果蘋果這樣做，這將是該股的另一個催化劑。

　　4、If you were to change something at your company, what would it be?

　　如果你要改變你的公司，你會怎么做?