英译汉 4.  Since there is no evidence that human cancer, as generally experienced, is infectious, many people believe that because viruses are infectious agents they cannot possibly be of importance of human cancer.
【正确答案】由于没有证据表明人类通常经受的癌症具有传染性，所以许多人相信，既然病毒为传染性病因，它们不可能与人类癌症有很大关系。
【答案解析】