Trees are good for the planet. They make clean air for us to breathe (呼吸). They give us the shade (阴凉处) we need on hot days. Planting trees makes the world a healthier place. They are not just good for people. Birds and other animals need trees too.

Today is Tree-planting Day. Would you like to plant a tree? The steps will show you how: Dig a deep hole; Loosen (弄松) the tree’s roots; Put the tree in the hole; Put soil around the tree; Water the tree’s roots.

Be sure to plant a kind of tree that grows naturally in your place. It is better for other plants and animals. 

1.Trees can make _________ for people.

A planet

B birds

C animals

D air

解析：选D。D 细节理解题。根据第一段第二句的“They make clean air for us to breathe”树制造干净的空气供我们呼吸。故选D。

2.We need trees most in _________.

A spring

B summer

C autumn

D winter

解析：选B。B 推理判断题。根据第一段第三句“They give us the shade we need on hot days. ”树在炎热的天气给我们提供阴凉处，炎热的天气主要在夏天，因此我们最需要树的时候是夏天。故选B。

3.There are ________ steps to plant a tree.

A 2

B 3

C 4

D 5

解析：选D。D 细节理解题。根据第二段的“The steps will show you how: Dig a deep hole; Loosen (弄松) the tree’s roots; Put the tree in the hole; Put soil around the tree; Water the tree’s roots.”可知，种树一共有五个步骤：挖一个深洞；把树根弄松；把树放进洞里；把土放在树的周围；给树根浇水。故选D。

4.What’s the best title (标题) for the passage?

A Good Trees.

B Plant a Tree.

C Trees and Birds.

D Who Need Trees?

解析：选B。B 主旨大意题。本文主要介绍了树的好处以及如何种树，结合选项可知“种一棵树”最符合文意。故选B。