含義不同、用法不同、介詞不同。by this way的意思是借著這種手段，表示被動；in this way的意思是用這個辦法，表示主動。by this way介詞為by；in this way介詞為in。

by this way

By this way, we can save a lot of paper work.

這樣做的話，我們可以省下很多書面手續(xù)。

Only by this way, can we hope to reduce the waste on campus.

只有通過這樣的措施，我們才有希望減少校園浪費。

By this way, the drawing efficiency can be improved.

采用這種方法，可以有效提高機械圖樣的繪圖效率。

And by this way you can

通過這種方法，你才可以。

in this way

He pulled my sleeve, attracted my attention in this way.

他扯了扯我的衣袖以引起我的注意。

In this way they can better apply theory to practice.

這樣他們就能更好地把理論運用到實踐中去。

In this way they brought into full play the initiative, wisdom and power of the masses.

這樣他們就使群眾的積極性、智慧和力量都充分發(fā)揮出來。

Only in this way can the experiment succeed.

惟有這樣做，試驗才能成功。