1.A hot potato
Speak of an issue (mostly current) which many people are talking about and which is usually disputed
2.A penny for your thoughts
A way of asking what someone is thinking
3.Actions speak louder than words
People's intentions can be judged better by what they do than what they say
4.Add insult to injury
To further a loss with mockery or indignity; to worsen an unfavorable situation.
5.An arm and a leg
Very expensive or costly. A large amount of money.
6.At the drop of a hat:
without any hesitation; instantly