Script (guión): Idioms, ‘all mouth and no trousers’. If someone is all mouth and no trousers then they talk about doing big and important things but they never do them. My friend Bill is always saying he's going to give up his job in the milk factory as he's going to go take his bike and tour the whole of Europe for a year. However he's all mouth and no trousers, as he's been saying this for the last ten years and he hasn't even got a bicycle.