这句英文句子谁来解释下?

问题描述:

这句英文句子谁来解释下?
In August,he pleaded a guilty to charges of engaging in wire fraud.to charges of engaging 是什么句子成分?

八月,他为自己参与电讯欺诈的控诉作无罪辩护.
a guilth tosth.(charges of engaging in wire fraud)