Off your rocker

If you are 'off your rocker' (a nickname for a rocking chair), it means whatever you're saying is completely wrong. It most likely originated with senior citizens, who often use rocking chairs.

Example:
-I may be completely off my rocker here, but I think your coworker has a crush on you.
-No, you're not off your rocker! I think so, too.

On the back burner

If you put something 'on the back burner' (which is the back part of the stove), it means that now you have to attend to other things first before you can get back to it.

Example:
-I was planning to replace my kitchen floor this summer, but now we have to get a new car.
-Well, I guess the floor will have to go on the back burner.

On the same page

Being 'on the same page' is a phrase used by one person to reassure that the listener is in agreement with them about something, understands or is thinking about something in the same way. It is usually used after there has been some discussion about something and an agreement has been reached.

Examples:
Okay, let's make sure everybody is on the same page. We'll meet back here tomorrow at 2:30 for rehearsal.

-Carol really needs to go to the doctor tomorrow. I think we're all on the same page about that.

Off the top of my head

'Off the top of my head' is used to refer to the first thing a person can think of.

Examples:
-Do we need anything at the grocery?
-Not off the top of my head.

-What do you want for your birthday?
-I can't think of anything off the top of my head.

He took another opportunity.

Saying that someone "took another opportunity" is a way of saying someone no longer works in a place. Since it is a vague response, there is no way to know if the person quit or was fired.

-Does Michael still work here?
-No, he took another opportunity.
-Oh, that's too bad! I really liked him!
-Yeah, we miss him, too.