Page 90 - English - Teaching Academic Esl Writing

76 CHAPTER 4
ery English sentence needs to have a verb to be grammatical. However,only the main verb is absolutely essential, and all other slots inside the verb phrase system are optional. For example,
Peter Peter Peter
Peter
should should have
has been
cooks/cooked. [The essential main verb] cook. [Optional should and the main verb]
cooked. [Optional should and have, and the main verb]
cooking. [Optional has, been, and -ing, and the main verb]
Inside the verb system, the optional slot is reserved for modal verbs (e.g., can, may, should) or the future tense marker, will. If this slot is occupied, the rest of the slots can contain only the baseform of the main verb (e.g., I/he should go, we/she can sing). If the slot is not occupied, the form of the main verb depends on the tense and number of the subject noun (e.g., / walk, he walks, they walked; I go, he goes, they went).
However, as noted in the examples earlier, the verb phrase can include more slots than just those for modals/future markers and the main verb. For this reason, the slot system has to allow for more options to account for various tense auxiliaries, such as was,have/has, or been because all sen- tence verbs have some sort of tense. For instance, even in the case of modal verbs, two options are possible (e.g., should cook or should have cooked, not to mention such complex constructions as will be cooking or will have finished/sung).
In effect, the tense of the verb is the first thing that needs to be identified because it determines what happens to the rest of the elements in the verb system. For example, What tense is used in the preceding text—the present or the
past?Aretimemarkersand adverbsfound toallowthetenseswitch?Identifying the
TLFeBOOK