答案 意思是 一定一直都在做某事She is so tired .She must has been working all the morning.她很疲劳了她一定工作了一个早上must have been doing 表示肯定的猜测并且猜测这种动作,或者行为一直持续到现在相关推荐 1must have been doing的用法是怎样的可以详细讲解一下吗?最好附带例句 反馈 收藏 ...
其实must have been done只是must have done的被动形式罢了.我说,你举出来的那几个例子:1那个就是must have been doing的结构是指某动作在过去某时间点开始,一直持续到现在,有继续持续下去的趋向,或者等这句话一说完这个动作就完成;2那个是加形容词 be expensive=很贵,must have been expensive= 一定是很贵的...
'must have been doing'用于对过去某一时间点或时间段内正在进行的动作的推测,而'must be doing'则用于对现在或将来某一时间点正在进行的动作的推测。 例如,'He must have been studying all night.'(他昨晚肯定一直在学习。)中的'must have been doing'表示对过去学...
must be doing:肯定某人正在做某事..He must be doing his homework.他一定在做他的作业 must have been doing:肯定某人一直在做的事..He must have been trying his best to study..他肯定一直都在尽力学习.. must表强烈的肯定,shall不那么强烈,could最弱..表推测的情况一般不用can ... 分析总结。 这里...
He must have had lunch. 他肯定吃过午饭了. must + 完成进行式(have been doing): 推测过去某一时刻正在进行的动作. It must have been raining at 8 yesterday morning.昨天早上六点钟时天肯定在下雨. 分析总结。 推测过去所发生的事情和已经完成的动作结果...
.must be doing:肯定某人正在做某事..He must be doing his homework.他一定在做他的作业 must have been doing:肯定某人一直在做的事..He must have been trying his best to study..他肯定一直都在尽力学习..must表强烈的肯定，shall不那么强烈，could最弱..表推测的情况一般不用can ......
这里涉及两个知识点：1： must have done 句型，这个句型表示对过去事实的肯定猜测，这句话翻译过来就是：我猜想你当时一定是走神了。因此这是对过去某一时刻正在发生的动作的猜测，因此涉及到的知识点是 2：must have been doing 表示对过去正在发生的动作的肯定猜测，结合刚才翻译，就可以理解了 ...
解析 简单说一下吧..must be doing:肯定某人正在做某事..He must be doing his homework.他一定在做他的作业 must have been doing:肯定某人一直在做的事..He must have been trying his best to study..他肯定一直都在尽... 分析总结。 他一定在做他的作业musthavebeendoing...
b.“must + have + done”表示对过去情况的推测。 He must have told my parents about it.他一定把这件事情告诉我的父母了。 c.“must + have + been doing”表示对过去正在发生事情的推测。 —Why didn’t you answer my phone call last night?昨晚你为什么没接我的电话? —Well, I must have been...
"must be doing"可以与各种时态(如过去进行时、将来进行时等)搭配使用,表示对某种情况或行为的不同时间维度的推测。 例如:He must have been studying last night.(昨晚他一定正在学习。) They must be having a party next week.(下周他们一定会举办派对。) 综上所述,"must be doing"是一个用于表示推测的...