be true with/of

题目

be true with/of
We notice this to be true very often with dogs and cats; but it is true with other animals as well.
这里的 this to 怎么理解 为什么有to,为什么不是 this be true with ..
very 和 often 是修饰 true的

答案

1）We notice this + to be ture...,to be ture 及以后是不定式作宾语从句,this 是指代上文的意思.2）也可以这么写：We notice that it is ture very ofter...3) very oftern 是描述this to be ture...