once in a blue moon: 偶然、千载一时
I don't usually hang out here, just once in a blue moon.
kill some time：消磨时刻
Where shall I go 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.
nick of time：紧要关头
His generous endowment of the laboratory came just in the nick of time.
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、日子寥寥无几
The old man' s days are numbered.
Down to the wire：最终时刻、挨近最终期限
I think the election will got right down to the wire.
He turned in the report at the eleventh hour.
From the word go: 一开始
He's been against the plan from the word go.
In the long run：长时刻
The product can help you to save money in the long run.
Jump the gun:草率行事、急于求成
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：从速
Shake a leg! The bus won't wait.
quick off the mark：立刻举动
Be quick off the mark if you hear of something promising.
Step on it：加快
If he didn't drive faster, we were going to be late, so I told him to step on it.
Time on one's hands：有空余的时刻
I've got extra time on my hands.
Under the wire：在截止日期前， the last minute
He applied the college just under the wire.
Until the cows come home:一向的、很晚很晚
This wine's delicious! I could drink it until the cows come home.