for

I bought this special set of paintbrushes for my sister who loves to paint.

(Chinese) 我为我那个热爱画画的姐姐买了这套特殊的画笔。

The research was conducted for the sole purpose of finding a cure for the disease.

(Chinese) 这项研究的唯一目的是找到治愈这种疾病的方法。

He was anxious, for he had never performed in front of such a large crowd before.

(Chinese) 他很焦虑，因为他以前从未在这么多人面前表演过。

It's not good for you to be too relaxed when you have such an important exam tomorrow.

(Chinese) 明天有这么重要的考试，你太放松对你没好处。