英语语法分析

The defoliation of millions of acres of trees by massive infestations of gypsy moth caterpillars is a recurring phenomenon in the northeastern United States.

在美国东北部，舞毒蛾毛虫的大规模侵扰导致数百万英亩的树木落叶，这是一个反复出现的现象。

Their first map focuses on Africa, where worm infestations are worst.

他们的第一批地图着手于非洲，因为那里是寄生虫感染最多的地方。

Rothamsted Research, home to the Broadbalk experiment, has been tracking aphid infestations for 50 years.

洛桑研究院的Broadbalk实验，五十年来一直在跟踪蚜虫的侵扰。