1 . The team was going to ________(探索) the wild mountain lying in the west. (根据汉语提示单词拼写)

2 . He came up to ________(问候，迎接) me. （根据汉语提示单词拼写）

3 . Second, don’t spend your vacation time in a place where everything is too expensive so as to ________(保持)a positive mood. (根据汉语提示单词拼写)

4 . There's a man at the reception desk who seems very angry and I think he means__ trouble.

A．making

B．to make

C．to have made

D．having made