(7) What are the forms of the verb?
In English there are several different kinds of verbs.  All verbs except modal auxiliary ("helping") verbs have at least three distinct forms: A few irregular verbs have only these three forms -- verbs like cut and put.  The past tense and the past participle forms of these verbs are the same as the simple forms.

Most verbs are regular.  Regular verbs and some irregular verbs (like bring) have four forms, the three above, a fourth form which serves as both the past tense and the past participle form:

A small number of irregular verbs have four forms, the top three and a past tense form which is distinct from the past participle form.  The simple form of this kind of irregular verb is used where a past participle form would be used. Some irregular verbs have five distinct forms:  the three forms that all verbs have and a separate past tense and past participle form.
Simple Form -s Form Past Tense Form -ing Form Past Participle Form
Regular help helps helped helping helped
carry carries carried carrying carried
clutch clutches clutched clutching clutched
Irregular cut cuts cut cutting cut
bring  brings brought bringing brought
run runs ran running run
fall falls fell falling fallen
drink drinks drank drinking drunk

The verb be
The verb be has more forms than any other verb.  It has a simple form, an -ing participle form, a past participle form, a first person singular present tense form, a third person present tense (-s) form, a plural present tense form, a singular past tense form, and a plural past tense form:

The modal auxiliaries
Each modal auxiliary has only one form*: can, could, shall, should, will, would, may, might, and must.