contact catalyst

例句：

1. 1. The scientist made contact with the alien life form.
   科学家与外星生命体取得了联系。
2. 2. The phone rang and I answered it, hoping to make contact with a friend.
   电话响了，我接了起来，希望能与一个朋友取得联系。
3. 3. They had no idea how to make contact with each other.
   他们不知道如何相互联系。