confirm, ascertain, substantiate 区别?

confirm, ascertain, substantiate 都有“确认、证实”的意思，怎么区分?

confirm和substantiate都含“证明或证实...是真实的或准确的”意思。

confirm指“用事实或证据来进一步证实或证明...是真实的”，如：confirm a rumour证实谣言。

substantiate指“列举事实以证实某一主张是有效的”， 如：The slanderer
cannot substantiate his tale. 那个诽谤者不能证实他的谎言。

ascertain指“探知, 发现; 确定，调查, 查明, 断定”，如：I ascertained that she was dead. 我断定她已经死了。

词性及解释 part of speech and definition vt. 证实, 确定, 批准, 使巩固 【计】 确认 【经】 证实 例句 sentences confirm letter of credit 确认信用证，保兑信用证 irrevocable and confirm credit 保兑不可撤销的信用证 to confirm an appointment 确定约会 confirm the truth of. 确定事情的真实情况。 our observations confirm that... 我们的观察证实... substantiate: [ sʌbs'tænʃieit ] v. 实体化,证实 词形变化: 名词:substantiation 动词过去式:substantiated 过去分词:substantiated 现在分词:substantiating 第三人称单数:substantiates 例句与用法: 1. can you substantiateyour accusations against him? 你指责他, 能提出事实根据吗? 英英解释: 动词substantiate: 1. establish or strengthen as with new evidence or facts 同义词：confirm, corroborate, sustain, support, affirm 2. represent in bodily form 同义词：incarnate, body forth, embody 3. make real or concrete; give reality or substance to 同义词：realize, realise, actualize, actualise 4. solidify, firm, or strengthen corroborate: [ kə'rɔbəreit ] v. 使坚固,确证,给确证与... 词形变化: 形容词:corroborative 名词:corroboration 动词过去式:corroborated 过去分词:corroborated 现在分词:corroborating 第三人称单数:corroborates 例句与用法: 1. his friend corroborated his guilt. 他的朋友证实了他的犯罪。 2. experiments have corroborated her predictions. 实验证实了她的预言。 英英解释: 动词corroborate: 1. establish or strengthen as with new evidence or facts 同义词：confirm, sustain, substantiate, support, affirm 2. give evidence for 同义词：validate 3. support with evidence or authority or make more certain or confirm 同义词：underpin, bear out, support