Should have, could have, and would have are sometimes called “modals of lost opportunity” because they describe situations when we are imagining that the past was different.
在该步骤中，要从最接近的现有技术和发明实际解决的技术问题出发，判断要求保护 的发明对本领域的技术人员来说是否显而易见。 判断过程中，要确定的是现有技术整体上
和前面的例子类似，由于上文被描述为需求，所以需要将上文中的”can”全部替换为”shall” 。 然而，这个例子中在b项中也包含了一个有关安全的陈述
Could Should Would | Exercises with answers Answers are at the bottom of the page. Exercise 1 Choose between could, should and would: 1. I swim well when I was a boy. 2. you like …
Modal verbs: Could Should Would (Exercises) Answers are at the bottom of the page. Exercise 3 Choose between could, should and would: 1. In the summer we always go camping. 2. you get …
更多内容请点击：SHOULD HAVE, WOULD HAVE, AND COULD HAVE