I think we should choose 3.

That's not bad either.

You can also test teachers.

After all, business English is business+English.

You don't have to take a long vacation as a teacher, but you should study hard.

I have a friend who plays all day and is still taking exams.

No matter what you study, you must work hard, and it is even more important to be angry.

We need to work hard.

PS: I'm just a poor scholar. The above views are for reference only.