他主动提出开车送我回家，我觉得这非常友善。

He offered to drive me home, ___which I thought was very kind.

我们正在推出一条新的产品线，我相信这会很成功。

We're launching a new product line, ___which I believe will be successful.

这部电影有一个出人意料的结局，我觉得相当巧妙。

The movie had a surprise ending, ___which I found quite clever.