He is very like his mother.

The company is badly in need of new blood.

英语中，某些程度副词可以修饰介词短语，但这个介词短语往往具有动词意味。例如两个例句的介词短语：

非常像；十分需要。

又如：

This tree is well above the other trees.  （远远高于）

这棵树远远高于别的树。

This idea is well worth considering.  （很值得考虑）

这个想法很值得考虑。

原来的问题是 extremely 能否修饰 of importance，这里of 引出事物的某种属性。不可同日而语。

不可以说：1. This letter is extremely of importance.

但可以说：2. This letter is extremely important.

                    3. This letter is of extreme importance.