I thought she was acting foolishly, but I 'bit my tongue' [='held my tongue'] and didn't say anything.
The news of their engagement 'set tongues wagging'. = 'Tongues were wagging' over their engagement.
He speaks English fluently but his 'mother tongue' [='native language, first language'] is Chinese.
(..) but she dead. Welcome. Hey! What about me? Don't you hold out on me, you big dummy nigger. Ooh, here come the boss man. You'll keep a civil tongue on my block. You get that one for free. But that's the last one. That's it? Just that little itty-bitty one? (..)1999 The Green Mile