b)  Should = good idea      Should not = bad idea 

 Ought to = less common 

Ought to=rare

Ex: You should study hard this semester 

 c)   Had better (not)= informal conversation = strong advice especially as warning = negative consequence if the advice or warning  is not followed 
*had always contracted and often omitted in formal conversation 
Ex: you ‘d better attend to class toddy.   

a) Ought to have or should not + past participle
 = past events or situations
= situations that were advisable but did not happen 

Ex: she ought to have studded hard, but she was sick.  

b) Shouldn’t have + past participle
=bad decision, express regret

Ex: she shouldn’t have stayed late at night.

c)   Should (not)=use to criticize. 

Ex: she should have taken mother suggestion. 

Ex: the university probably won’t accept any international students   

b) Should (not) and ought to = certain. 

Ex:  the device should be ready by  Saturday. 

 

c) could, may(not)and might (not)= last certain. 

Ex: the movies may be staring at night. 

  Normal that clauses can function as a subject and an object. They often begin with word that.

  Ex: I think that running is tiring.
        The sign means that the elevator is out of order. 

2. What the form of “that clauses”

 a. That clauses have their own subject and verb.

 Ex: Many Chinses people think that Chengdu is beautiful city.

 b. In conversation and informal writing, that is often omitted. In academic writing, that is not omitted sometimes.

 Ex: I think running is tiring.
       I cannot forget that I once visited a shop which is full of wands.

3. That clauses after adjectives and nouns

 a. we can use a that clause after adjectives that express emotion or certainty such as certain, clear, and evident. The form is It+be+certain adjectives+that.

 Ex: It is clear that we have too much homework.

 b. we can use a that clause after nouns that describe thoughts and ideas such as belief, hope. and concern. The form is noun+be+that.