杨桐最近在英国照片:Sit up 和Stay up有区别吗

意思上有区别，用法上没有区别；在表达上有区别
sit up 是熬夜的意思，是有事可做的熬夜，是不得已
stay up 没有特别的什么事要做，也许就是闲着，或是失眠等原因，反正是睡不着，一直醒着。
所以,要想说，我昨天通宵学习啦，就用前面的那个

坐起；端坐；使坐起；使端坐
rise or cause to rise from a lying to a sitting position; sit upright
· The patient is able to sit up and take nourishment now.
病人现在已经能够坐起来吃东西了。
· She sat up in bed and looked at the clock.
她从床上坐了起来，看了看钟。
· He told the children to sit up and not slouch.
他叫孩子们坐端正，不要弯腰曲背。
· He's much better today; he's able to sit up in bed now.
他今天好多了，现在可以在床上坐起来了。
· He sat up from his chair.
他从靠背椅上坐起来。

迟睡；熬夜
stay up after the usual time for going to bed
· The doctor sat up all night with the patient.
医生彻夜守护病人。
· The students sat up late watching TV yesterday evening.
昨晚学生们因看电视睡得很晚。

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不去睡觉；不休息
not go to bed; refrain from taking rest
· I'll be late home, but please don't stay up for me.
我将晚回，但请不要为了等我而不睡觉。
· We stayed up until after midnight.
我们呆到午夜之后才去睡觉。
· Tell the servant to stay up until I get back,I may be very late.
告诉佣人，等我回去再睡，我可能要很晚才回去。

停留或保持在上面
remain up in position
· The hook won't stay up; it keeps on falling down.
钩子扣不住，老是要掉下来。

不倒；不沉
not fall or sink
· These houses stayed up in the quake.
这些房子在地震中没有倒塌。

都熬夜 没区别 不过stay up 用的稍微多点