A word that can be the head of a verb phrase (VP). Verbs denote actions (e.g., jump), sensations (e.g., taste), and states (e.g., understand). In many languages, verbs inflect for tense, mood, aspect, or agreement with their subject. We can distinguish between auxiliary and main verbs. Auxiliary verbs (also called helping verbs) typically accompany another verb and express person, number, mood, or tense. In the sentence He is looking at me, is is an auxiliary verb, and looking is the main verb.