Hard and fast
If a rule is hard and fast, it is fixed and definitive.
Hard feelings
Hard feelings are feelings of resentment.
Hard up
When you are hard up you are short of money.
Make a hash of
To make a hash of something is to make a mess of it.
Pass the hat round
To pass the hat round is to collect contributions of money.
Take your hat off to
This is an expression used to express your admiration for someone.
As mad as a hatter
If somebody is as mad as a hatter, they are completely insane.
Bury the hatchet
To bury the hatchet is to end a quarrel.
Play havoc with
To play havoc with something is to completely disrupt it.
Make hay while the sun shines
To make hay while the sun shines is to make good use of an opportunity while it lasts.
Come to a head
To come to a head is to reach a crisis.
Go to someone’s head
When success goes to your head, it makes you feel too proud.
Head over heels
When you are head over heels in love with someone, you are madly in love with them.
A head start
A head start is an advantage gained at the beginning.
Make head or tail of
When you can’t make head or tail of something, you can’t understand it at all.
Heap something on
To heap praise on someone is to give them too much praise.
- The media heaped praise on the actor.
At heart
He is kind at heart. (= He is kind in his real nature.)