摘要：to be expected or required to do/be sth according to a rule, a custom, an arrangement, etc.
be supposed to do/be sth
1.
（按规定、习惯、安排等）应当，应，该，须
to be expected or required to do/be sth according to a rule, a custom, an arrangement, etc.
Public spending is supposed to fall, not rise, in the next few years.
在接下来的几年里，政府开支应该会下降，而不是上升。
The National Election Council is supposed to certify the results of the election
全国选举委员会应对选举结果出具证明。
All this was supposed to work magic
这一切被认为会创造奇迹。
I'm supposed to have handed in a first draft of my dissertation
我本该把论文的初稿交上去了。
Theoretically, the price is supposed to be marked on the shelf
照理说，价格应该标在货架上。
You're supposed to buy a ticket, but not many people do.
按说应当买票，不过买的人不多。
The tests are supposed to provide a basis for the assessment of children
这些测试应该可以为评价儿童提供一个基础。
We're supposed to be running a business here. I've got work to do
我们在这里应该是要经营公司。我有一堆的事情要做。
I didn't know I was supposed to aim at the same spot all the time.
我不知道自己应该一直瞄准同一目标。
They are supposed to be here at about half four.
他们应该在4点半左右到达这里。
I thought we were supposed to be paid today.
我以为我们今天会领到薪水呢。
I thought we were supposed to be living in a democracy.
我还以为我们应该是生活在一个民主国家里。
I was supposed to do some work this weekend but I couldn't be arsed.
这个周末我本应该干点事，不过我不愿去找那个麻烦。
The first debate was supposed to have been held on Tuesday.
第一场辩论本该在星期二就举行了。
I was supposed to be writing a letter but I'm afraid I got sidetracked.
我本来应该在写信，但后来恐怕是分心干别的去了。
These new friends of hers are supposed to be very rich.
她的这些新朋友想必都很富有。
Regular use of conditioner is supposed to give your hair more body.
经常使用护发素能使头发更浓密。
This combination of qualities is generally supposed to be extremely rare.
一般认为，同时具有这样一些品质极为罕见。
Don't try to tell me what I'm supposed to be feeling
别跟我说我到底该作何感想。
Journalists are supposed to be politically neutral.
新闻工作者在政治上应持中立态度。
It was supposed to be a surprise but the children gave the game away.
本想给人一个意外，可孩子们把计划泄露了。
How am I supposed to know ─ I'm not psychic!
我怎么会知道呢，我又没有特异功能！
The engine doesn't sound like it's supposed to.
发动机听起来不对劲。
You were supposed to be here an hour ago!
你本该在一小时以前就到这儿！
How was I supposed to know you were waiting for me?
我哪知道你在等我？
‘Yes and no.’ ‘ What is that supposed to mean ?’ (= showing that you are annoyed)
“是但又不是。”“这算什么意思呢？”
2.
一般认为；人们普遍觉得会
to be generally believed or expected to be/do sth
I haven't seen it myself, but it's supposed to be a great movie.
这部电影我没看过，不过人们普遍认为很不错。
3.not be supposed to do sth
不准；不应当；不得
to not be allowed to do sth
You're not supposed to walk on the grass.
不准践踏草地。
'You're not supposed to say that,' she said primly.
“你不该讲那样的话。”她一本正经地说。
I'm not officially supposed to be here.
按公事说，我是不该到这里来的。
Life in the great outdoors isn't supposed to be luxurious.
美好的户外活动不必很奢侈。
4.be presumed to do sth据推测，被推定
The temple is presumed to date from the first century BC.
据推测这座寺庙建于公元前1世纪。
The company is presumed to be still solvent.
公司被推定有偿还能力。
来源：翅膀英语