Bù zhīdào dàjiā juédé zuò nǚrén zuìdà de bēi'āi shì shénme?
I don't know what you think is the difficult thing about being a woman?
I'm confused as to why 做 is in this sentence; it seems to serve some kind of grammatical function I'm not aware of. It looks like it could be omitted without problem. I also feel a bit of a mismatch between both 做 and 是 in the sentence.
Question: Why is 做 in the sentence 不知道大家觉得做女人最大的悲哀是什么？
Looking up 做 using the PeraPera Chinese Popup Dictionary:
to do; to make; to produce; to write; to compose; to act as; to engage in; to hold (a party); to be; to become; to function (in some capacity); to serve as; to be used for; to form (a bond or relationship); to pretend; to feign; to act a part; to put on appearance
Among many definitions, there's "to be", "to act as", and "to produce" on the list, which seem closest in meaning. The 做 in the given sentence functions something like "is" (approximately "is the greatest annoyance"), which is typically performed by 是 (and this also occurs in the sentence). However, we obviously can't just interchange 是 and 做 throughout Chinese.
I'm more familiar with using 做 to form a verb (e.g. 做饭 "cook food" and 做工业 "do homework") rather than in this case 做悲哀 which seems along the lines of "give rise to annoyance".