1. To Express Ability
1.1. CAN
1.1.1. Use
1.1.1.1. Express present ability
1.1.1.1.1. [use example]
1.1.1.2. [use description 2]
1.1.1.2.1. [use example]
1.1.2. Form
1.1.2.1. Subject + Modal can + Base Form of the Verb
1.1.2.1.1. He can win the war
1.1.2.2. Subject + Modal can't + Base Form of the Verb
1.1.2.2.1. Jon can't be dishonest
1.1.2.3. Auxiliary verb can + subject + Base Form of the Verb
1.1.2.3.1. Can he defeat a white walker?
1.2. BE ABLE TO
1.2.1. Use
1.2.1.1. Express ability
1.2.1.1.1. [use example]
1.2.2. Form
1.2.2.1. Subject + VERB TO BE + ABLE TO + Base Form of the Verb
1.2.2.1.1. He is able to win the war
1.2.2.2. Subject + VERB TO BE NEGATIVE + ABLE TO + Base Form of the Verb
1.2.2.2.1. He is not able to lie
1.2.2.3. VERB TO BE + Subject + ABLE TO + Base Form of the Verb
1.2.2.3.1. Is he able to return from death?
1.3. COULD
1.3.1. Use
1.3.1.1. We can use could to talk about general ability that existed in the past
1.3.1.1.1. She could read when she was three
1.3.1.2. [use description 2]
1.3.1.2.1. [use example]
2. For Requests
2.1. CAN
2.1.1. Use
2.1.1.1. [use description 2]
2.1.1.1.1. [use example]
2.1.2. Form
2.1.2.1. Subject + Modal can + Base Form of the Verb
2.1.2.2. Subject + Modal can't + Base Form of the Verb
2.1.2.3. Auxiliary verb can + subject + Base Form of the Verb
2.2. MAY
2.2.1. Use
2.2.1.1. [use description 2]
2.2.1.1.1. [use example]
2.2.2. Form
2.3. COULD
2.3.1. Use
2.3.1.1. [use description 2]
2.3.1.1.1. [use example]
2.3.2. Form
3. To Express Possibility
3.1. WILL
3.1.1. Use
3.1.1.1. [use description 2]
3.1.2. Form
3.2. SHOULD
3.2.1. Use
3.2.1.1. [use description 2]
3.2.1.1.1. [use example]
3.2.2. Form
3.3. MAY
3.3.1. Use
3.3.1.1. Express Possibility in the Future
3.3.1.1.1. Everybody may be working from home in 2030
3.3.2. Form
3.3.2.1. Modal + Future Continuous Tense
3.4. COULD
3.4.1. Use
3.4.1.1. Express Possibility in the Future
3.4.1.1.1. I could be living in Germany next year
3.4.2. Form
3.4.2.1. Modal + Future Continuous Tense
3.4.3. Use
3.4.3.1. Express Possibility in the Past
3.4.3.1.1. It could have been her
3.4.4. Form
3.4.4.1. Could + Have + Past Participle
3.5. MIGHT
3.5.1. Use
3.5.1.1. [use description 2]
3.5.1.1.1. [use example]
3.5.2. Form
3.6. CAN
3.6.1. Use
3.6.1.1. [use description 2]
3.6.1.1.1. [use example]
3.6.2. Form
4. Talk about Hypotetical Situations
4.1. 1rst Conditiional
4.2. Unreal Events
4.2.1. 2nd Conditional
4.2.2. 3rd Conditional
5. To Express Advice
5.1. SHOULD
5.1.1. Use
5.1.1.1. Give Advice or Make a Suggestion
5.1.1.1.1. We should change your habits
5.1.2. Form
5.1.2.1. Subject + SHOULD + Base Form of the Verb
5.1.2.1.1. You should turn off the tap
5.1.2.2. Subject + SHOULD NOT+ Base Form of the Verb
5.1.2.2.1. You should not buy books you never read
5.1.2.3. SHOULD +Subject + Base Form of the Verb
5.1.2.3.1. Should I buy that thing?
5.2. OUGHT TO
5.2.1. Use
5.2.1.1. Give Advice or Make a Suggestion ( less formal than SHOULD)
5.2.1.1.1. You ought to know a little more of what our scientists say about all tha
5.2.2. Form
5.2.2.1. Subject + OUGHT TO + Base Form of the Verb
5.3. HAD BETTER
5.3.1. Use
5.3.1.1. For giving URGENT ADVICE when you believe that something bad will happen if the person does not follow the advice
5.3.1.1.1. You had better stop watching so much TV or your grades will suffer
5.3.2. Form
5.3.2.1. Subject + HAD BETTER + Base Form of the Verb
6. To Express Necessity
6.1. MUST
6.1.1. Use
6.1.1.1. [use description 2]
6.1.1.1.1. [use example]
6.1.2. Form
6.2. CAN'T
6.2.1. Use
6.2.1.1. [use description 2]
6.2.1.1.1. [use example]
6.2.2. Form
6.3. HAVE TO
6.3.1. Use
6.3.1.1. [use description 2]
6.3.1.1.1. [use example]
6.3.2. Form
6.4. HAVE GOT TO
6.4.1. Use
6.4.1.1. [use description 2]
6.4.1.1.1. [use example]
6.4.2. Form
7. To Express Assumptions
8. authored by @adasanchez
9. To Express Permissions
9.1. COULD
10. To Express Regrets
10.1. SHOULD
10.1.1. Use
10.1.1.1. Criticize Past Actions Or Situations
10.1.2. Form
10.1.2.1. SHOULD + Have + Past Participle
10.1.2.1.1. You should have followed your Doctor's Advice
10.1.2.2. SHOULD NOT + Have + Past Participle
10.1.2.2.1. You shouldn't have had so much to drink last night