Idioms A

about time = finally.
It's about time they got married. They've been living together for five years.

about to = almost, soon
He's just about to blow out the candles on his birthday cake.

after all = after everything that happened / despite the facts
This was an expensive car, but I decided to buy it after all.

all of a sudden = something happens quickly.
All of a sudden, the boy slipped while riding on his skateboard.

as if = similar; something has a similar quality.
His headache was so bad it felt as if his head was in a vise.

as soon as = after something happens; immediately after
Nguyen started to eat his food as soon as it was served to him.

as well as = and
She's strong as well as beautiful.