白白: in vain, for nothing
【高33】语气副词 / adverbs
Tone colorsā tone 1á tone 2ǎ tone 3à tone 4a neutral
白白 + verb says that an action or a resource is lost for nothing: it brings no result and nothing in return. There is always a note of regret: 她忘了关水龙头，白白浪费了很多水 (she forgot to turn off the tap and wasted a lot of water). This is the sense, "in vain, to no result", that this page teaches.
It comes before a verb of loss or wasted effort: 浪费, 损失, 牺牲, 放弃, 等, 跑, 忙, 扔……, most often followed by 了 and a quantity (白白损失了很多钱). 白白地 + verb also occurs. In speech the single 白 is also used, shorter and punchier: 白跑一趟 ("a wasted trip"), 白忙了. 白白 is a little more emphatic and takes longer verb phrases.
白白 judges a result, so it never fits a success. Don't confuse it with the adjective 白白的 ("nice and white", as in 白白胖胖).
Examples
她忘了关水龙头，白白浪费了很多水。
Tā wàng le guān shuǐlóngtóu, báibái làngfèi le hěn duō shuǐ.She forgot to turn off the tap and wasted a lot of water for nothing.
这次投资失败了，让公司白白损失了很多钱。
Zhè cì tóuzī shībài le, ràng gōngsī báibái sǔnshī le hěn duō qián.The investment failed, and the company lost a lot of money for nothing.
他早就走了，我在车站白白等了两个小时。
Tā zǎojiù zǒu le, wǒ zài chēzhàn báibái děng le liǎng ge xiǎoshí.He had left long before; I waited two hours at the station for nothing.
别白白放弃这个机会。
Bié báibái fàngqì zhè ge jīhuì.Don't throw this chance away for nothing.
客户临时取消了合同，大家白白忙了一个星期。
Kèhù línshí qǔxiāo le hétong, dàjiā báibái máng le yí ge xīngqī.The client cancelled the contract at the last minute, so everyone worked a week for nothing.
糖色糊了，不倒掉的话，一锅好肉就白白浪费了。
Tángsè hú le, bù dàodiào de huà, yì guō hǎo ròu jiù báibái làngfèi le.The caramel has burnt; if you don't throw it out, a whole pot of good meat will be wasted for nothing.
Common mistakes
✗ 我们白白赢了比赛。 → 白白 judges a loss: a win is not wasted (✓ 我们白白练了三个月，还是输了).
✗ 他白白很高兴。 → ✓ 他白白高兴了一场。 (白白 qualifies a verb that names the loss, not a plain state).
✗ 浪费白白了很多水。 → ✓ 白白浪费了很多水。 (the adverb goes before the verb).