sick as a dog
As easy as ABC
Piece of cake
Bun in the Oven
best thing since sliced bread
Feeling under the weather
Break a leg
Once in a Blue Moon
head in the sand
spill the beans
like 2 peas in a pod
Let the cat out the bag
The early bird catches the worm
When pigs Fly
Eagle Eyed
I smell a Rat
Finding a needle in a haystack
Rome wasn't built in a day
Kill 2 Birds with one stone
Elephant in the room
Like a Fish out of water