People use their mouths for many things. They eat, talk, shout and sing. They smile and they kiss.
In the English language, there are many expressions using the word mouth. But some of them are not so nice.
For example, if you say bad things about a person, the person might protest and say "Do not bad mouth me."
Sometimes, people say something to a friend or family member that they later regret because hurts that person's feelings.
Or they tell the person something they were not supposed to tell.
The speaker might say: "I really put my foot in my mouth this time."
If this should happen, the speaker might feel "down in the mouth." In other words, he might feel sad for saying the wrong thing.
Another situation is when someone falsely claims another person said something.
