lip service 从字面上来看是嘴唇的服务，真实含义是空口应酬话，开空头支票。

【例句】
It shows that we are taking action and not just paying lip service.
事实证明我们正在采取行动，而不是口头上说说。

Today many friendships are not real; people are merely paying lip service to one another.
今天许多的友谊都不纯真；人们彼此只是说些应酬话。