A lot more exercises and fuller notes and tips are needed for this section Peggy white
Yes, I think Spanish "Verbs: Modal" needs to be split into at least 10 lessons. I've been stuck on the second lesson for two weeks now, and I know that if I ever do pass it, I won't have learned it, because there seems to be at most one example sentence for each form of the verb.
This lesson seems to have too many concepts all mixed together, as well as some ambiguous examples, and to add to the confusion it accepts some incorrect responses. I've been through the tree many times and still fail this one sometimes :-/ This lesson, together with the subjunctive and condition lessons, would greatly benefit from a redesign.