of course = yes; a strong yes. Similar to "certainly."

Woman: Do you love me?

Man: Of course, I do! Give me a kiss!

woman kissing

off and on = not a regular schedule; temporary; similar to "sometimes."

He’s been sleeping off and on while trying to finish a big project.

He works off and on for a software company.

man sleeping

on the other hand = however; but. Used for showing contrast

Visiting China for the Olympics this year would be fun; on the other hand, it might be really expensive. We should wait until next year.


on the dot = exactly on time

Ms. Johnson expects her employees to arrive at work every morning on the dot–or earlier.


on time = not late; not too early.

Blake wasn’t on time for his date with Stephanie, so he brought her some flowers.

In fact, he’s never on time.

man with flower

once again = another time; once more.

Once again, he’s hurt his back by trying to lift something heavy. His wife keeps telling him not to even try.


open to = ready to accept new ideas.

It’s a wise person who is open to new ideas.

Are you open to learning new things?

("Open to" can be followed by a gerund. In the example above, "learning" is a gerund.)


Next: P