These materials were originally used on the Delta Module One course run by Business Talk Milan. The course has now closed.
To fully understand the explanations here, you need first to have worked through the materials on tense and time (and understand Lewis' view of the relationship between them) and on auxiliary verbs.
Work through each task sheet, referring to grammars etc if necessary, before you look at the accompanying Commentary. Ask yourself - do they just list the meanings of the modal verbs or do they really explain why they have those meanings - why for instance can differs in use from could. If you don't have a grammar in book form, try the Cambridge Online Grammar-
Don't cheat and just read the Commentary - there's far too much complex information to take in just by reading. You need to work actively on this area if it is to be memorable.
And don't try and do them all in one sitting. Take one area at a time - no more than one a day - in the order they're presented here, and work on them thoroughly. After you complete each section, look again at your grammar. What are the similarities or omissions?
a) Possibility: Can / Could / Able to / May / Might... and more
Expressing Possibility - Task.pdf - Commentary.pdf
b) Prediction and Volition : Be Going to / Will / Would ...
Work through this handout (including reading the two articles indicated on Will and Be going to): Will, Be Going to, Would.pdf before going on to the presentation which discusses the questions on Would.
Click on the link below to view the presentation:
NB: I am aware that the volume of the presentation in this section is very low. On my computer it is just audible - better with headphones. Make sure your computer sound is set to maximum.
c) Obligation and Necessity : Must / Have to / Need (to)
Must, Have to, Need to - Task .pdf - Commentary.pdf
d) Prediction and Volition - or Obligation? : Shall / Should.. and more
Shall, Should - Task.pdf - Commentary.pdf
Note: Keep in mind that modal concepts are not only expressed through modal verbs or their semi-modal or periphrastic equivalents. The same concepts that we looked at above can also be expressed through other word classes - eg: possibility can be expressed through the adverbs maybe or perhaps: John's late. Maybe he missed the early train. Other adverbs like certainly, definitely, possibly can express or intensify other degrees of certainty - eg: I certainly didn't do it. And so can adjectives such as possible/ikely/liable/certain - eg: I'm likely/liable to be late tonight. Lexical verbs like insist, recommend, etc can express degrees of volition. Compare: You must stop doing that / I insist that you stop doing that. And so on.