beef is coarse slang for "boast" or "brag."
begin: Commence is frequently substituted for begin work where the change should not be made. Begin is applied to order of time; commence relates to the work on hand with reference to its subsequent completion. The man who strikes the first blow begins a fight, but both parties to a law suit commence litigation at the moment when they severally undertake the first step.
begin by him: This is incorrect; say, "begin with him."
behave: Strictly means "comport." When used with a reflexive pronoun as, "Behave yourself," this word is correctly applied. When the pronoun is omitted as, "Will you behave?" the sentence is incomplete and the expression a mere colloquialism.
being: The phrases "is being built," "was being built," and kindred forms of English imperfects passive are condemned by certain critics as recent and unwarranted; Fitzedward Hall points out that they are neither recent nor unwarranted, and have been used by the best writers for a century. He says: "Prior to the evolution of is being built and was being built, we possessed no discriminate equivalents of ædificatur and ædificabatur; is built and was built, by which they were rendered, corresponding exactly to ædificatus est and ædificatus erat."—Modern English, App., p. 350.