Idiomatic Expressions

[wil16]

Hi. I'd like to know the meanings of the following idiomatic expressions so that I know their meanings to eventually use them in daily conversations.
They are: cha ching, Beat it, Lemon, All system go, Can't push one's way out of the paper bag, Think big.

Thanks for your help.

[beascarpetta]

Beat it! (SLANG) Go away!
cha ching (slang)

Lemon
a) a very foolish person (informal,UK)
I felt such a lemon when I discovered I'd missed my appointment.

b) something that does not work (informal, US)
Only one of his inventions turned out to be a lemon.

couldn't act/argue/fight your way out of a paper bag (humorous) if someone couldn't act, argue, fight etc. their way out of a paper bag, they act, argue, fight etc. very badly

[fromatto]

Hi. I'd like to know the meanings of the following idiomatic expressions so that I know their meanings to eventually use them in daily conversations.
They are: cha ching, Beat it, Lemon, All system go, Can't push one's way out of the paper bag, Think big.

Thanks for your help.

Here are some suggestions, although I'm sure others will improve on them:

cha ching: is the sound of a cash register and indicates 'a lot of money'.
beat it: means 'go away'.
Lemon: is a failure. 'It was a bit of a lemon'.
All systems go: everything is functioning normally and we can proceed. I think this comes from the American space program.
Can't PUNCH his way out of a paper bag: he is physically weak. He is useless.
Think big: think of the whole picture, not just the details. What would you like to do if money were no object ?