Question

6. They’ve won their last three matches,      I find a bit surprising.

Answer 1

6. which句意：他们赢得了最后的三场比赛，我觉得这确实有点儿让人意外。

which指代前面的"They've won their last three matches"，作find的宾语。

that不能用于非限制性定语从句中。