Joke Collection Website - Mood Talk - What idioms are there to describe lip service?

What idioms are there to describe lip service?

Just talk on paper-be an armchair strategist

On paper. Metaphor is empty talk, which can't solve practical problems. It is also a metaphor that empty talk cannot become a reality.

[Source] Cao Qingxue Qin's Dream of Red Mansions: "There are such poets here; But I go to talk on paper every day. "

Mere oral statements cannot be guaranteed/used as evidence.

[Interpretation] There is no evidence in the mouth. Just prove it in kind.

[Source] Qing Li Garbo's "Officialdom in Appearance" 27 th time: "If there is no evidence; Pupils are afraid to talk to teachers. "