也可理解为固定句式吧！这类表达主要用于表示某人或某物的某种特质（好或不好），其中的 a lot 也可换成 much, little, very little等，如说成：

It says a lot for sb / sth that…

It says very little for sb / sth that…

It says much for sb / sth that…

典型例句：

It says a lot for him that he never gave up.

It says a lot for her that she stayed in the game even though she was injured.

It says much for Brookner's skill that the book is sad, but never depressing.

It didn't say much for their efficiency that the order arrived a week late.

It doesn’t say much for my powers of observation that I had no idea what was going on.