Which principal part is this verb form?

(is) cutting

A.
past participle

B.
present participle

C.
past

D.
present

To determine the principal part of the verb form "is cutting," we need to understand the different principal parts of verbs in English. Generally, there are four principal parts of a verb: the base form, the past tense, the past participle, and the present participle (also known as the -ing form).

The base form is the simplest form of the verb and is used in the present tense, such as "cut." The past tense refers to the verb form used to indicate actions that have already happened in the past, like "cut" in this case. The past participle form is used to form the present perfect and past perfect tenses and is often combined with an auxiliary verb like "has" or "had," such as "cut." The present participle, which ends in -ing, is used to form the progressive tenses and gerunds, such as "cutting."

In the given verb form "is cutting," the verb "cutting" ends in -ing, indicating that it is a present participle form. Therefore, the correct answer is B. present participle.