How to Use 'Should', 'Ought to', 'Supposed to' and 'had better'

source: Oxford Online English       2017年2月9日
See the full version: http://www.oxfordonlineenglish.com/sh...
We use the verbs 'should', 'ought to', 'supposed to' and 'had better' to say what you or other people think is the right thing to do.
That means these verbs express advice, opinion, criticism or (for 'had better'), warnings or threats.
'Should' and 'ought to' have the same meaning, although 'ought to' is much more formal and is not commonly used in spoken English.
'Supposed to' refers to what other people think is right, while 'should' expresses what you think is right.
'Had better' expresses the idea that something bad will happen if you don’t do what I say. This is why 'had better' can also be used to make threats or give someone a warning.

In this lesson, you'll learn more about:
- What 'should' means and how it compares to 'ought to', 'supposed to' and 'had better'.
- When you can/can't use 'ought to' instead of 'should'.
- The difference between 'should' and 'supposed to'.
- The meaning of 'had better' and how to use it.

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