should 的用法

Question

I should be obliged if you would send them to me. if he should come ,give him this letter should ministers decide to instigate an inquiry,we would welcome it. 三句中should的用法?

Answer 1

四种:
1.应该：用来表示义务或职责：
You
should
send
her
a
note.
你应该给她留一个条
2.用于表示可能性或期望：
They
should
arrive
at
noon.
她应该在中午到达
3.用于表示可能性或可能发生的事件：
If
she
should
fall,
then
so
would
I.
如果她失败了，那我也会失败
4.用于使一个直接或直率的陈述变得婉转：
I
should
think
he
would
like
to
go.
我倒是认为他愿意去