1Although ethics classes are common around the world, scientists are unsure if their lessons can actually change behavior; evidence either way is weak, relying on contrived laboratory tests or sometimes unreliable self-reports.
主干主语：scientists；谓语：are unsure；宾语从句：if their lessons can actually change behavior；后一分句主语：evidence；谓语：is；表语：weak
结构Although引导让步状语从句。主句含if引导的宾语从句。分号后为并列分句，relying on为现在分词短语作原因/伴随状语，修饰weak，or连接两类证据来源。either way指正反两方面证据。
译文尽管世界各地普遍开设伦理课，科学家仍不确定这些课能否真正改变行为；无论正反，证据都很薄弱，往往依赖人为设计的实验室测试，或有时并不可靠的自我报告。
考点although让步从句与主句的转折关系 · 分号连接并列分句；现在分词短语作状语
2They chose this particular behavior for three reasons, according to study co-author Eric Schwitzgebel, a philosopher at the University of California, Riverside: students attitudes on the topic are variable and unstable, behavior is easily measurable, and ethics literature largely agrees that eating less meat is good because it reduces environmental harm and animal suffering.
主干主语：They；谓语：chose；宾语：this particular behavior
结构according to…为插入语，其后a philosopher…为同位语。冒号后三个并列分句说明reasons。第三分句含that宾语从句，其中because引导原因状语从句。students attitudes为原文写法。
译文据该研究合著者、加州大学河滨分校哲学家埃里克·施维茨格贝尔所说，他们选择这一特定行为出于三点：学生对这一话题的态度多变且不稳定，行为易于测量，而且伦理文献大体认同少吃肉是好事，因为它能减少环境损害和动物痛苦。
考点according to插入与同位语说明身份 · 冒号后三项并列；that从句嵌套because原因从句
3Schwitzgebel predicted the intervention would have no effect; he had previously found that ethics professors do not differ from other professors on a range of behaviors, including voting rates, blood donation and returning library books.
主干主语：Schwitzgebel；谓语：predicted；宾语从句：the intervention would have no effect
结构分号连接两个并列分句。后一分句含that引导的宾语从句；do not differ from…on…为比较结构；including引导介词短语，列举behaviors的具体方面。
译文施维茨格贝尔曾预测这次干预不会有效果；他此前发现，伦理学教授在一系列行为上与其他教授并无不同，包括投票率、献血以及归还图书馆的书。
考点predicted后省略that的宾语从句 · differ from…on…；including列举同位说明
4Psychologist Nina Strohminger at the University of Pennsylvania, who was not involved in the study, says she wants the effect to be real but cannot rule out some unknown confounding variable.
主干主语：Nina Strohminger；谓语：says；宾语从句：she wants…but cannot rule out…
结构句首职业头衔作同位说明。who引导非限制性定语从句。says后为省略that的宾语从句，内含but连接的并列谓语wants与cannot rule out；wants后为复合宾语the effect to be real。
译文宾夕法尼亚大学心理学家尼娜·施特罗明格并未参与该研究，她说自己希望这一效应是真的，但又无法排除某种未知的混淆变量。
考点非限制性定语从句who was not involved · want + 宾语 + to be；rule out混淆变量
5Schwitzgebel suspects the greatest impact came from social influenceclassmates or teaching assistants leading the discussions may have shared their own vegetarianism, showing it as achievable or more common.
主干主语：Schwitzgebel；谓语：suspects；宾语从句：the greatest impact came from social influence…
结构suspects后省略that。原文influence与classmates之间无空格，后半可理解为对social influence的补充说明：leading the discussions为现在分词作后置定语；may have shared为推测；showing为现在分词作结果/伴随状语。
译文施维茨格贝尔猜想，最大影响来自社会影响——主持讨论的同学或助教可能分享了自己的素食做法，表明这是可以做到的，或比想象中更普遍。
考点suspects后宾语从句；may have done表对过去的推测 · 现在分词leading/showing作定语与状语