once in a blue moon: 偶尔、千载难逢
I don't usually hang out here, just once in a blue moon.
kill some time：消磨时间
Where shall I to kill some time?
at the drop of a hat：动辄
He was ready to quarrel at the drop of a hat.
burn the midnight oil：熬夜
You shouldn't burn the midnight oil, actually you should sleep
nick of time：紧要关头
His generous endowment of the laboratory came just in the nick of time.
around the corner: 快到来了
The exam is just around the corner, I really need to cram for it.
spur of the moment：一时冲动
He bought the car on the spur of the moment.
days are numbered：气数已尽、日子屈指可数
The old man' s days are numbered.
Down to the wire：*后时刻、接近*后期限
I think the election will t right down to the wire.
He turned in the report at the eleventh hour.
From the word : 一开始
He's been against the plan from the word .
In the long run：长期
The product can help you to save money in the long run.
Jump the gun:草率行事、操之过急
Don't jump the gun. We have to be patient for a while.
put something On hold：稍等
The decision was put on hold until a meeting of the party's central committee.
Shake a leg：赶快
Shake a leg! The bus won't wait.
quick off the mark：马上行动
Be quick off the mark if you hear of something promising.
Step on it：加速
If he didn't drive faster, we were ing to be late, so I told him to step on it.
Time on one’s hands：有空余的