Daily English. 日常英语

"a" vs "the"

"a" 表达不具体的东西 比如说 I saw a movie

last night.

因为你刚说的是a movie，所以对方可以参考这个movie，用着"the"
How was the movie?

Writing:

There was a market crash last week.
The crash provided a good buying opportunity.
The buying opportunity allowed us to profit immensely.

看一看，先介绍新的topic用 "a". 后来参考这个话题用着"the"