:to say that you will act in a forceful and aggressive way说话口气强硬
When the subject is national security, all the candidates talk tough. [=they say that they will act aggressively to support national security]当涉及国家安全时，所有候选人的口气都很强硬。
— often + on
The new mayor talks tough on crime.这位新市长在犯罪问题上口气强硬。