不惜: not hesitate to, at the cost of
动词 / verbs
Tone colorsā tone 1á tone 2ǎ tone 3à tone 4a neutral
S + 不惜 + (V) + cost/sacrifice，(也要) + goal
不惜 ("not begrudge, not spare") means being ready to pay a high price for a goal: "at the cost of", "not shrink from", "go as far as".
The complement is a sacrifice: 不惜一切代价 (at all costs), 不惜花重金, 不惜牺牲. The judgement can be positive (devotion) or negative (dubious means) depending on context.
Examples
有的企业为了利润，不惜牺牲环境。
Yǒu de qǐyè wèile lìrùn, bùxī xīshēng huánjìng.Some companies sacrifice the environment for profit without hesitation.
他不惜一切代价，也要查明真相。
Tā bùxī yíqiè dàijià, yě yào chámíng zhēnxiàng.He's determined to uncover the truth at any cost.
父母不惜借钱，送孩子出国读书。
Fùmǔ bùxī jiè qián, sòng háizi chū guó dú shū.The parents even borrowed money to send their child abroad to study.
Common mistakes
✗ 不惜 + something pleasant: ✗ 他不惜度假 → the complement must be a cost.
✗ Confusing 不惜 (spare no) with 可惜 (what a pity).