尤为 and 越发: especially, all the more
【高10】【高11】副词 / adverbs
Tone colorsā tone 1á tone 2ǎ tone 3à tone 4a neutral
尤为 and 越发 are two written degree adverbs that intensify. 尤为 singles one item out above the rest (“particularly, above all”): 他对自己的要求尤为严格. 越发 says that a degree grows further because of what has just happened (“all the more, increasingly”): 听到这个消息，同学们越发有热情了.
尤为 goes before an adjective or a verb of attitude (尤为重要, 尤为突出, 尤为重视), often after 对……来说. It compares implicitly with the rest, so it does not take 比. It is more written than 尤其 (hsk5-g40), which can also open a noun phrase (尤其是孩子).
越发 needs a starting point already in place: a cause (随着年龄的增长), a moment (读着读着) or a circumstance. It stands before an adjective or a verb of feeling, often followed by 了 (越发觉得……, 越发有热情了). It is the written side of 越来越 (hsk2-g32), which describes a gradual rise with no cause named.
Examples
对孩子来说，睡眠尤为重要。
Duì háizi láishuō, shuìmián yóuwéi zhòngyào.For children, sleep is especially important.
这个问题在大城市尤为突出。
Zhège wèntí zài dà chéngshì yóuwéi tūchū.This problem is especially acute in big cities.
他对自己的要求尤为严格。
Tā duì zìjǐ de yāoqiú yóuwéi yángé.He is especially strict with himself.
听到这个消息，同学们越发有热情了。
Tīngdào zhège xiāoxi, tóngxuémen yuèfā yǒu rèqíng le.Hearing the news, the classmates grew all the more enthusiastic.
随着年龄的增长，他越发不喜欢出去旅行了。
Suízhe niánlíng de zēngzhǎng, tā yuèfā bù xǐhuan chūqù lǚxíng le.As he grows older, he likes going on trips less and less.
读着读着，我越发觉得韩愈不是在平静地讲道理，而是在着急。
Dúzhe dúzhe, wǒ yuèfā juéde Hán Yù bú shì zài píngjìng de jiǎng dàolǐ, ér shì zài zháojí.The more I read, the more I felt that Han Yu was not calmly making an argument but fretting.
Common mistakes
✗ 这个问题比那个尤为重要。 → ✓ 这个问题尤为重要。 (尤为 already singles one item out, so it does not combine with 比).
✗ 他今天越发高兴。 → ✓ 听到好消息，他越发高兴了。 (越发 needs a starting state and a cause that raises the degree).