1. As Cool As a Cucumber:

very calm or very calmly, especially when this is surprising.

Example: She walked in as cool as a cucumber, as if nothing had happened.

2. Hold Your Horses:

used to tell someone to stop and consider carefully their decision or opinion
about something.

Example: Just hold your horses, Bill! Let’s think about this for a moment

3. Kick the Bucket:

a euphemistic, informal, or slang term meaning ‘to die’.

Example: Charlie finally kicked the bucket. He had cancer, you know.

4. Blue in the Face:

weakened or tired after trying many times.

Example: You can tell her to clean her room until you are blue in the face, but she won’t do it.

5. Storm in a Teacup:

a lot of unnecessary anger and worry about a matter that is not important.

Example: My brother and sister had a big argument about the television yesterday, but it was just a storm in a teacup.

6. Bob’s Your Uncle:

used to mean that something will happen very quickly and simply.

Example: Just tell them you’re a friend of mine and, Bob’s your uncle, you’ll get the job.

7. Head In The Clouds:

living in a fantasy. To be separate from reality, to dream.

Example: He’s not right for this role, he has his head in the clouds

8. Dead As A Doornail:

completely dead.

Example: The fox in the road was as dead as a doornail.

9. A Piece Of Cake:

something very easy to do.

Example: The test was a piece of cake.

10. Heart In Your Mouth:

feeling nervous or scared.

Example: My heart’s in my mouth ever time it rings