Idioms J

jam up / jam = get stuck; a mechanical failure
The toilet got all jammed up so we had to call a plumber.
The highways were jammed with traffic during rush hour.

jerk / jerk around = to cause problems for someone; to be mean, not nice
Stanley got tired of being jerked around by his boss, so he quit his job.
His boss was a jerk.

join in = become a part of a group; invite
While her friends were talking, she wasn't able to join in the conversatioin because she had to finish doing something on her laptop.

joke around = to say something funny, not serious.
A: It's snowing outside?! Are you kidding me?
B: Yeah, I'm just joking around.

jump on = buy or get something quickly.
When we found out this house was for sale, we jumped on it and our offer was accepted.

just around the corner = very soon.
Her due date is just around the corner. She'll probably have her baby within the next couple of weeks.

just in = new information suddenly avaialble. Usually used on radio and TV news.
"Just in... a tornado has been sighted in our area. Take shelter immediately!"