阅读理解

      Do you need friends? I'm sure your answer is "Yes, of course. Everybody does! "You need friends when you play and when you work. If you have friends, you will feel happy. If you have no friends, you will feel lonely.

      Do you know how to make friends? There is only one good way—You make friends by being friendly.

      A friendly person is interested in other people. He is always helpful. If you want to make friends with a new classmate, you can talk with him, tell him about the other classmates in your class and try your best to be helpful to him.

_______ Lily _______ Sam likes popular songs, so they went to Lin Feng's concert together last night.

质量较大的鸽子与质量较小的燕子在空中飞行，如果它们的重力势能相等，那么（　　）

位于北方地区的，我国最大的盐场是（　　）