To accidentally reveal a secret or spoil a surprise.
Let the cat out of the bag
To struggle to speak clearly because of a dry or sore throat, or needing to clear your voice.
Have a frog in your throat
Something large and expensive that is more trouble than it's worth, especially because it’s hard to maintain or get rid of.
A white elephant
Very clever and good at deceiving or tricking others.
As cunning as a fox
To deal with a difficult situation directly and bravely, without avoiding it.
Take the bull by the horns
Don’t assume something will definitely happen before it actually does.
Don’t count your chickens (before they are hatched)
Someone who appears kind or harmless but is actually dangerous or untrustworthy.
A wolf in sheep's clothing
To suspect that something dishonest or suspicious is happening.
Smell a rat
The biggest or most important part of something.
The lion's share
To waste time trying to do something that is no longer possible or useful.
Flog a dead horse