Animals
"Hold your horses"
Wait, or be patient.
"Break a leg"
Good Luck!
"Sick as a dog"
Really sick
"Keep and eye on"
Watch
"Raining cats and dogs"
Raining hard, heavily
"I'm all ears"
I'm listening
"Let the cat out of the bag."
tell a secret
"Cost and arm and a leg"
Expensive
"Barking up the wrong tree"
Looking in the wrong place for the answer.
Took on something too difficult