1. To know something like the back of your hand
If you know something like the back of your hand, you know it very well.
We mainly use this expression to talk about our knowledge of a particular place.
"I've lived in Hong Kong for ten years, I know it like the back of my hand".
2. To have your hands tied
You can use this expression to say that you are unable to help in a situation.
"I'm sorry I can't give you a bonus this year, my boss won't allow it. My hands are tied".
3. To give someone a hand
If you give someone a hand, you help them with a task.
"This is really heavy, could you give me a hand"?
4. To get out of hand
A way of saying that a situation got out of control.
"Everyone drank too much at the party, I'm not surprised it got out of hand".
5. One the one hand..on the other hand
You can use these phrases to express conflicting opinions about a subject or to recognise the pros and cons.
"On the one hand, moving to the city would provide us with more job opportunities but on the other hand, I do love living in the country side".
6. To wash your hands of something
If you wash your hands of something, you stop being responsible or involved in it.
"You can decide whether or not to sell the building, I'm washing my hands of the matter".
7. Talk to the hand
This is a rude way of dismissing what a person is saying.
"Talk to the hand because the face isn't listening"!