Pull someone's leg

(fool someone)

Hey, Al, I was invited to be a judge for the Miss America Beauty Pageant!
Oh, really? Come on, you're pulling my leg! 
No, honestly. Do you really think that I'm trying to fool you with a ridiculous story? 
Well, you've told me foolish stories before. 
I can assure you that this one is for real.

Play it by ear

(improvise as one goes along)

Let's go to the movies, agreed? 
Sure. And what'll we do after that? 
Oh, I don't know. Let's play it by ear. 
Well, I would like to have a more definite plan of action. 
Don't be like that. It's always more fun not knowing what to expect and deciding what to do as we go along.

Get off someone's back

(stop bothering someone)

Hey, John. I'm bored. Come on, let's go out and do something. 
Sorry, I'm right in the middle of studying for a physics exam. I won't be able to make it tonight. 
You've been studying for a long time. Why don't you take a break? Come on, Let's go. Forget studying for a while.
Look! Get off my back! I can't go anywhere!
OK, I'll stop bothering you only if you promise to let me know the minute you're finished.

Go to the dogs

(become run-down)

Have you seen their house lately? It's really gone to the dogs. 
It's true that it has become run-down and in serious need of repair, but I'm sure that it can be fixed up to look like new. 

Fishy

(strange and suspicious)

When the security guard saw a light in the store after closing hours, it seemed to him that there was something fishy going on. He called the central office and 
explained to his superior that he thought something  strange and suspicious was occurring.

All Thumbs

(clumsy)

Hey, Bea. Can you help me out? I don't seem to be able to button up the back of my dress.
Sure. Let's see if I can do it for you.
I guess I'm all thumbs because I'm so nervous. I'm already late for my date.
Well, I suppose that being so nervous would make you clumsy and awkward. But don't worry I'm sure your date will wait.

Not To Have A Leg To Stand On

(to have no good defense for one's opinions or actions)

Tom maintains that the firm owes him some back wages for having worked overtime. However, he won't have a leg to stand on unless he can prove that he put in all those extra hours. He doesn't stand a chance of getting his money without a strong foundation of facts to support his position.

Stick Out One's Neck

(take a risk)

How come they're asking me to act as their guide through the jungle? Evidently they think you're the only one who can lead them to the lost temple. That jungle has danger lurking around every corner
Why should I stick my neck out for them? They didn't pay me for my services. They know that you would be taking a great risk and could possibly get hurt, but you're the only one with enough knowledge to take them to their destination. I'm sure you'll be amply rewarded

Shake a Leg

(hurry)

Mary, you always take such a long time to put on your makeup. Come on, shake a leg!
I'll be finished in a minute. Be patient. You've got to hurry or else we won't arrive on time to see the last show.