English verbs have no Gender distinction. In addition, the deployment of the Person, Number, Mood and Tense attributes is extremely limited. In the past tense, there are no distinctions of Person and Number, except for the solitary case of the verb `to be', which has a singular form `was' distinct from the plural form `were'. In the present tense, except again for the verb `to be', only two forms of each verb occur: the `-s' form in the third person singular, and the base form for all other combinations of person and number. These observations apply to the indicative mood. As for the other moods (subjunctive and imperative), the subjunctive is rarely used and the imperative is invariable. The subjunctive is also invariable, except for a vestigial past subjunctive of the verb `to be', in the singular use of `were'. Because of extensive syncretism in the English verb, the historical paradigms of Person, Number, Case, and Mood are barely sustainable in the description of modern English. The base form, if regarded as multifunctional, has at least the following morphological functions for all verbs except `to be':
Since it is impractical, however, given the current capabilities of tagging software, to resolve automatically the ambiguity of these six morphological functions, it is a common practice to assign a single value to the base form, or else to assign two values, one for the finite and one for the non-finite functions. Because of this, the tables below show two tagsets: one tagset representing the 6 attribute-values above, and a reduced tagset (`RTags'), which resembles most tagsets so far used for the English language in reducing the six values to two.