claim 作动词有两个方向：①声称/宣称（claim that... = 声称……，隐含「尚未证实」）；②索取/主张权利（claim compensation = 索赔）。作名词：a claim = 一项声称/主张（make a claim = 提出主张）。关键语气：claim 含「说话者宣称但听者可能存疑」的意涵——比 say 更中性，比 assert 更常用，是议论文中引述他人观点时的核心动词。
释义
1
v.声称；宣称（claim that / to do）
The company claims that its products are entirely eco-friendly.
该公司声称其产品完全环保。
2
v.索取；主张（对……的权利）
She claimed compensation after the accident damaged her car.
事故损毁了她的车后，她索取了赔偿。
3
n.声称；主张（claim that / claim to sth.）
His claim that he had never met the suspect was later disproved.
他声称从未见过嫌疑人的说法后来被推翻了。
语感
claim that = 「据某人称……」，隐含存疑语气——议论文引述争议观点时必用
声称宣称索取主张（权利）
议论文三个关键搭配：claim that（声称……）引述存疑观点；make a claim（提出主张）；support / back up a claim（支撑某主张）。注意 claim 的存疑语气：Researchers claim that... 暗示「研究者这么说，但尚待证实」；如果已被证实，用 find / show / demonstrate。区别：claim ≠ complain（抱怨）——两者形似但含义截然不同。
陷阱
⚠️claim vs complain 形近混用
✗
The customer claimed about the poor service.
顾客对差劲的服务提出了抱怨。
「抱怨」用 complain about；claim 是「声称/索取」，不能说 claim about
✓
The customer complained about the poor service.
顾客抱怨了糟糕的服务。
⚠️claim 的存疑语气不可忽视
The experiment showed that caffeine improves short-term memory.
Some researchers claim that excessive screen use is linked to declining attention spans in children, though the causal relationship has yet to be confirmed.
关键搭配：claim that ... though
claim that ... though ... 是议论文引述争议观点并附上保留意见的经典框架；claim 的存疑语气与后半句的「尚未证实」相呼应。