extraneous source(s)

• 外源

extraneous source(s)的用法和样例：

例句

1. The biogeochemical absorption of outer source iodine by spinach through fertilizing solid iodine in soil and spraying of liquid outer iodine in spinach leaves was studied.
   摘要通过在土壤中施放固体外源碘和对叶片进行液体外源碘的喷洒，研究了菠菜对外源碘的生物地球化学吸收。