Historically, English modals came from a special class of verbs in Ger- manic, the ancestor of English and the other Germanic languages. Modals have always differed from ordinary verbs, to the point where they now belong to a special category of their own. Modals and verbs differ in the range of forms that Sentence: 4.24: Fritz may get a promotion.
they exhibit. English verbs appear in a number of distinct forms, whereas modals have a single, invariant form. For instance, modals never end in-s,even in sentences with third-person singular subjects.
To include the modal in our grammar, we simply expand the rule for auxil- iary to account for tense markers (past and present) and modals, as shown: AuxÆtense (M)
With this modification to our rules, we can describe sentences such as 24: 24. Fritz may get a promotion.
Analysis of this sentence is shown in the following tree diagram on the next page.
A question that often arises in the analysis of expanded verb phrases is why the tense marker is placed in front of the verb rather than after. The past parti- ciple suffix -ed/-en, after all, comes at the end of a verb, not at the beginning. The answer is that there is no simple way to capture schematically the rela- tions among tense, modals, and verbs. Whenever a verb has a modal, the modal is tensed, not the verb. If our description put tense after the verb, we would solve nothing—we would still have the question of how tense jumps over the verb and attaches to the modal. The placement of tense at the head of the VP is a matter of convention; placing it elsewhere in the VP would not en- hance the description.
What we learn here is that structural analyses are at best an approximate de- scription of the language we actually use. If we wanted to account for the fact that the...