Here are some common idiomatic expressions.
When you are about to do something, you are on the point of doing it.
- I was about to leave.
- She was about to call the police.
According to X means as said by X or in the opinion of X. Note that this expression cannot be used to give your own opinion.
- According to the minister, the government is going to crack down on corrupt officials.
- You have to do everything according to the terms and conditions of the agreement.
- According to the preacher, there is only one God.
Account for (something)
To account for something is to provide an explanation for it.
- You have to account for your absence from work.
After all means ‘we must not forget that…’
- You don’t have to invite him to your party. After all, he doesn’t invite you.
All of a sudden
If something happens all of a sudden, it happens without advance warning.
- All of a sudden, it started raining.
As a matter of fact
As a matter of fact means actually.
- As a matter of fact, I have never been to a concert.
As far as
As far as means to the extent or degree of something.
- As far as I know, Peter has no interest in politics.