adj.外来的；无关的
Reductant from an extraneous source is introduced. 外来的还原剂被引进来。
Because of the extraneous and uncontrolled factors, those may affect the dependent variable. 由于许多外来的无法控制的因素，这些因素可能影响应变因素。
The only extraneous item I may carry is a gift. 我带的唯一与旅行无关的物件是礼物。
Extraneous null statements are not always harmless. 无关的空语句并非总是无害的。
n.外部(支节)
