stay in bed 和stay in the bed 有什么不同?可以是stay on bed

我有不同的意见．
stay in bed 其实强调的是一种”卧床”的状态．
stay in the bed 强调的重点的这张床．（不是别的床，而是特指的床．）
stay on bed 没有这个说法．

stay in bed 休息
stay in the bed 生病

这个问题主要在于理解定冠词的意义
定冠词是表特指,生硬的翻译过来就是 "呆在那张床上"
那么从字面看,就看不出在床上做什么.
而没有定冠词,则表明在床上睡觉.
这和英语的表达习惯有关
你习惯就好了

stay in the bed 和 stay on bed 都是错的,英语有很多固定结构,要记不要想当然.
stay in bed:
呆在床上,卧床休息
Examples:
1. She'll have to sing for her supper if she comes to stay with me--I'm certainly not going to let her stay in bed all morning.
如果她要来同我一起住，吃饭可得干活－－我当然不会让她整个上午都呆在床上。
2. The doctor told you to stay in bed, and he knew best.
医生叫你卧床休息，他最清楚。
3. The doctor told you to stay in bed, and he knows best.
医生叫你卧床休息，他最清楚。
4. Take this medicine every fours hour and stay in bed for two day.
每隔四小时服用这些药，卧床休息两天。
5. I'll stay in bed as long as I like there's no law against it.
我在床上爱呆多久就呆多久--谁也管不著.
6. Unlike me, my husband likes to stay in bed.
我丈夫与我相反, 喜欢睡懒觉.