Once in a ... moon.(not very often, very rarely)
Once in a blue moon.
Once in a black moon.
Take it with a ... of salt.(don't always believe something is true, use caution)
Take it with a pile of salt.
Take it with a grain of salt.
Cross that ... when you come to it. (don't worry about something until if happens)
Cross that book when you come to it.
Cross that bridge when you come to it.
Curiosity ... the cat. (being curious can be dangerous and get you into trouble)
Curiosity killed the cat.
Curiosity jumped the cat.
Let ... dogs lie. (keep out of the situation, don't interfere with the problem)
Let sleeping dogs lie.
Let sleeping dogs lie.
... on the bandwagon.(to follow a trend)
Ski on the bandwagon.
Jump on the bandwagon.
Let's ... the knot. (get married, have a wedding ceremony)
Let's cut the knot.
Let's tie the knot.
It's a ... of cake.(its easy)
It's a piece of cake.
It's a slice of cake.
Actions ... louder than words.(what a person does is sometimes more important that what they say)
Actions yell louder than words.
Actions speak louder than words.
The best thing since ... bread.(to show enthusiasm about something)
The best thing since banana bread.
The best thing since sliced bread.
The ball is in your .... (Your turn to take action of a situation)
The ball is in your court.
The ball is in your mouth.
Feeling ... the weather. (feeling sick, unwell)
Feeling on top of the weather.
Feeling under the weather.
On the .... (undecided or uncertain)
On the road.
On the fence.
Bite off more than you can .... (To take on more responsibility than you can handle)
Bite off more than you can chew.
Bite of more than you can watch.
At the ... of a hat.(to happen instantly)
At the drop of a hat.
At the toss of a hat.
Don't put all your eggs in one .... (put all your efforts in one thing)
Don't put all your eggs in one basket.
Don't put all your eggs in one refrigerator.
Kill ... birds with one stone.(to solve to goals in a single effort)
Kill small birds with one stone.
Kill two birds with one stone.
I ... a rat. (a feeling of suspicion, not trusting ones actions)
I chase a rat.
I smell a rat.
Burn the ... oil. (to work or study late into the night)
Burn the house oil.
Burn the midnight oil.
It's the ... of both worlds.(to get advantages of two separate situations)
It's the best of both worlds.
It's the opposite of both worlds.
... the hook. (out of trouble)
Stuck on the hook.
Off the hook.
You're ... up the wrong tree. (being misguided , to lead in the wrong direction)
You're barking up the wrong tree.
You're smelling up the wrong tree.
As ... as a rock. (something that is extremely strong, firm, stable, and reliable)
As small as a rock
As solid as a rock.
It's a ... in the bucket. (a very small amount compared with what was expected)
It's a drop in the bucket.
It's a stick in the bucket.
It's a ... in disguise. (something bad that has good results)
It's a blessing in disguise.
It's a bee in disguise.
... your tongue.(keep your mouth shut on purpose)
Cut your tongue.
Bite your tongue.
Every cloud has a ... lining. (difficult or sad times often have a happy side to them)
Every cloud has a silver lining.
Every cloud has an invisible lining.