African Differed Tribal Group Preference Gutman Derived West

意群训练： This preference for exogamy , Gutman suggests , may have derived from West African rules governing marriage , which , though they differed from one tribal group to another , all involved some kind of prohibition agains t unions with close kin.

标志： This preference for exogamy , Gutman suggests, may have derived /from West African rules (governing marriage),［which , though they differed from one tribal group to another, all involved some kind of prohibition (against unions with close kin)］/.

译文： 这种对于异族通婚的偏好 ，G认为 ，有可能是来源 /于（管辖婚姻的）西非的规定 ，［该规定 尽管从一个部落到另外一个部落各不相同 ，但都涉及到 一些（反对近亲结婚的）禁忌］/。

解释： 本句有两个插入语，第一个插入语Gutman suggests割裂了主句的主语和谓语。West African rules后跟着两个修饰成分，第一个是分词修饰（governing marriage），第二个是以which引导的非限定性定语从句，从句中出现了第二个插入语though they differed from one tribal group to another ，又割裂了从句引导词与从句谓语之间的联系。