学术自由并不意味着可以突破伦理界限,尤其是在涉及人体实验时。Xuéshù zìyóu bìng bù yìwèizhe kěyǐ tūpò lúnlǐ jièxiàn, yóuqí shì zài shèjí réntǐ shíyàn shí.Academic freedom does not mean one may break ethical boundaries, especially when human experiments are involved.
朋友之间也应该有界限,不能什么都问。Péngyou zhījiān yě yīnggāi yǒu jièxiàn, bù néng shénme dōu wèn.Even between friends there should be boundaries; you cannot ask about everything.
这两种颜色之间的界限很模糊,几乎分不清。Zhè liǎng zhǒng yánsè zhījiān de jièxiàn hěn móhu, jīhū fēn bù qīng.The boundary between these two colours is very blurred, and they are almost impossible to tell apart.