finiteness in English

Every verb form in English falls on one side of the finite line. A finite form carries tense and can head an independent clause; a nonfinite form carries none and cannot. The nonfinite set has three members, the plain form used as an infinitive, the gerund participle and the past participle, and nothing sits between the two categories. The obligatoriness is recorded as pervasive for that reason: there is no unmarked verb form, because there is no third option and no verb escapes the contrast.

The exponence is another matter, and it is the honest qualification this record has to make. English inflection distinguishes the two categories in only a few cells. The third person singular present and the past tense are unambiguously finite by their endings. Everywhere else the finite present is identical to the plain form, so for most lexemes the tensed and untensed forms are the same string and the contrast is invisible in the morphology. It is nonetheless real, and the language provides several tests that read it directly: only a finite verb inverts with the subject in a question, only a finite verb takes the negative clitic, and only a finite clause can stand alone. Where the lexical verb offers no ending the language supplies the auxiliary do, which exists largely to carry finiteness where nothing else can.

The verb be is the one lexeme where the distinction is fully visible, with distinct forms for the present, the past and the plain form. It is the exception that makes the category legible, and a description built on it alone would overstate how much of the language marks this dimension. The state is recorded as explicit because a dedicated inflected form does exist and does mark the value, not because the marking is uniform.