Yes, definitely.
Disclaimer
I am not nearly as proficient in classical Chinese, so my answer is limited to modern Chinese.
IMHO, 未 is more commonly seen in formal context and is often used with 曾 or 從, as in 未曾 or 從未.
For example,
單純的你，未曾憂鬱過。
You're such a simple person; you've never been depressed.
人生自古以來，從未順遂。
Since the ancient times, life (of a human) has never been smooth.
Note that the adjectives act similarly to a verb, as suggested by WangYudong above. I don't think 長 and 短 are verbs per se.