1. Used to
1.1. Uses
1.1.1. Past situation that no longer exists
2. May
2.1. Uses
2.1.1. Polite request (only with I or we)
2.1.2. Formal permission
2.1.3. 50% or less certainty
3. Might
3.1. Uses
3.1.1. 50% or less certainty
3.1.2. Polite request (rate)
4. Should
4.1. Uses
4.1.1. Advisability
4.1.2. 90% certainty (expectation)
5. Ought to
5.1. Uses
5.1.1. Advisability
5.1.2. 90% certainty (expectation)
6. Had better
6.1. Uses
6.1.1. Advisability with threat of bad result
7. Be supposed to
7.1. Uses
7.1.1. Expectation
7.1.2. Unfulfilled expectation
8. Must
8.1. Uses
8.1.1. Strong necessity
8.1.2. Prohibition (negative)
8.1.3. 95% certainty
9. Have to
9.1. Uses
9.1.1. Necessity
9.1.2. Lack of necessity (negative)
10. Have got to
10.1. Uses
10.1.1. Necessity
11. Will
11.1. Uses
11.1.1. 100% certainty
11.1.2. Willingness
11.1.3. Polite request
12. Be going to
12.1. Uses
12.1.1. 100% certainty (prediction)
12.1.2. Definite plan (intention)
12.1.3. Unfulfilled intention
13. Can
13.1. Uses
13.1.1. Ability/possibility
13.1.2. Informal permission
13.1.3. Informal polite request
13.1.4. Impossibility (negative only)
14. Could
14.1. Uses
14.1.1. Past apility
14.1.2. Polite request
14.1.3. Suggestion (affirmative only)
14.1.4. 50% or less certainty
14.1.5. Impossibility (negative only)
15. Be able to
15.1. Uses
15.1.1. Ability
16. Would
16.1. Uses
16.1.1. Polite request
16.1.2. Preference
16.1.3. Repeated action in the past
16.1.4. Polite for "want" (with like)
16.1.5. Unfulfilled wish
17. Shall
17.1. Uses
17.1.1. Polite question to make suggestion
17.1.2. Future with I or we as subject