Be

Be is a versatile term in English that can refer to the verb "to exist" or to the chemical element with symbol Be. As a verb, be functions as a copula linking a subject with a predicate, and as an auxiliary helping form various tenses and voices. It also appears in fixed phrases and in expressions of appearance, identity, or state.

In grammar, be is highly irregular: the base form is "be"; present tense forms include "am," "is," and "are"; the past tense forms are "was" and "were"; the participles are "been" and "being." It is used as a main verb to denote existence or identity (I am here; This is a book) and as an auxiliary to form continuous tenses (she is singing) and passive voice (the ball was thrown). It also appears in subjunctive or conditional constructions.

Be is the chemical symbol for beryllium, a lightweight alkaline earth metal with atomic number 4. Beryllium is notable for its stiffness and high melting point, and it forms alloys with aluminum and other metals used in aerospace, electronics, and X-ray equipment. It occurs in minerals such as beryl and bertrandite and is extracted through mineral processing and smelting. Its compounds can be toxic if inhaled; proper safety measures are required in its handling.

The etymology of be traces to Old English beon and wesan, related to many Germanic languages, and it has cognates across West Germanic languages. The word is among the most fundamental in English, forming the backbone of many grammatical constructions and a key component of philosophical and mathematical discourse.