talking too much, esp about unimportant things 喋喋不休的, 饶舌的（尤指对琐事）becoming garrulous after a few glasses of wine

garrulity / gəˈruːlətɪ; ɡəˋrulətɪ/, garrulousness ns [U] talkativeness 絮叨; 饶舌; 多嘴.
garrulously adv.

English has many adjectives that share the meaning "given to talk" or "talking." "Talkative" may imply a readiness to talk or a disposition to enjoy conversation, while "loquacious" suggests the power of expressing oneself articulately, fluently, or glibly. "Voluble" suggests a free, easy, and unending talkativeness, and "garrulous" implies talkativeness that is dull, rambling, or tedious. "Garrulous," by the way, derives from the Latin verb "garrire," which means (no surprise here) "to chatter" or "to babble."

Example sentence:
With a few judicious revisions, a good editor can often transform. garrulous writing into elegant prose.
Miss Thompson, loud-voiced and garrulous, was evidently quite willing to gossip.
My garrulous neighbour had given away the secret.
He is really too garrulous.