多项选择题
Which of the following statements about Old Faithfulare correct?（）
A.It’s the name of a geyser in Yellow Stone National Park. B.It’s named after a man who was faithful. C.It’s the first geyser receiving a name. D.It erupts at regular intervals of time.
多项选择题 What are the two reasons to shape the Grand Canyon?（）
判断题 UNESCO designated Redwood National Park a world heritage site because of its rare ecosystem and cultural history.
单项选择题 How deep is the Grand Canyon?（）
