译文修改如下，修改说明附后。

In order to improve our English, it is critical to spend more time reading, writing, listening and speaking. Besides, it is very important to learn by heart as many good articles as possible. If we don't have an enormous number of good English writings in our memory, we cannot express our thought in English freely. It is also very helpful to summarize our learning experience. For in so doing, we can figure out which learning approach is more effective and produce the most desirable result.

1 原翻译四个more doing有重复之嫌。

2 besides和also意义重复，删去一个。

3 some和as many意义冲突，故删去some。宾语后移至状语by heart之后，使结构平衡。

4 中文原文中使用了我们和你，翻译成英文时应人称一致，都用第一人称复数。用memory免去brain和heart的选择。用have sth in our memory这个结构。

5 前面结构为it is critical to spend, it is important to learn, 这里应该继续用不定式结构it is also useful to do sth。边学边总结用summarize our learning experience更为简洁。

6 第一句不定式作目的状语为悬垂修饰语，但这种用法现在已经为人们所接受。故保留。