求人帮忙不要这样理直气壮地说话，不满意你可以不采纳。这只是一点小小的建议，冒犯之处请多多原谅。
这句话由三个句子组成
第一句是多重复合句，其结构如下：
时间状语从句：Whenever I met one of them who seemed to me at all clearsighted, 其中：
【主句】I met one of them
【定语从句】who seemed to me at all clearsighted（短语包括seem to sb. 和at all）
主句：I tried the expertment of showing him my Drawing Number One, which I had always kept. I would try to find out, so, ifthis was a person of true understanding.
【主句】I tried the expertment of showing him my Drawing Number One,
【非限制性定语从句】which I had always kept.
第二句是也是复合句
主句：I would try to find out, so, （find out是短语，但是后面丢了一个名词）
条件状语从句：if this was a person of true understanding.
第三句还是复合句
让步状语从句：whoever it was,
主句：he, or she, would always say: "That is a hat."
