Expressing Wasted Efforts with “bái”

你现在才开始准备，前面那些时间不是都白浪费了吗？

Nǐ xiànzài cái kāishǐ zhǔnbèi, qiánmiàn nàxiē shíjiān bú shì dōu bái làngfèi le ma?

You are only starting to prepare now. Wasn’t all that earlier time wasted?

我跟他说了半天，结果他一句都没听进去，真是白说了。

Wǒ gēn tā shuō le bàntiān, jiéguǒ tā yí jù dōu méi tīng jìnqù, zhēn shì bái shuō le.

I talked to him for a long time, but he did not take in a single sentence. I really spoke in vain.

这次会议要是没有结果，我们这些准备就全白做了。

Zhè cì huìyì yàoshi méiyǒu jiéguǒ, wǒmen zhèxiē zhǔnbèi jiù quán bái zuò le.

If this meeting produces no result, all our preparation will have been for nothing.