根据材料内容，选择最佳答案。
Helping others is easier than you think. You don't need to wait to become a rich man like Bill Gates to help
poor. You can become a volunteer, you can donate (捐献) your time, you can donate your old clothes and so on.
And in doing so, you can become a better and happier person.
Choose some people to support. for example, homeless people, poor children and so on. All of these are
suitable (合适的).
Decide what you are able to give. Yes! Sometimes it isn't only money-you can donate your time as a
volunteer, you can donate your knowledge teaching poor children, you can donate your old clothes, you can
donate food or you can share a meal with a hungry child.
Tell people about it. Tell your friends or your children. Put it in your blog or on your website. In this way,
the good work you do will be multiplied (增加)!
1. People usually think helping others is _______. [ ]
A. difficult
B. easy
C. interesting
D. exciting
2. How can you help others of you are poor according the passage? [ ]
A. Donate your money.
B. Talk to them.
C. Donate your time.
D. Play with them.
3. What's the meaning of the underlined word "homeless"? [ ]
A. 家境贫寒的
B. 无家可归的
C. 无依无靠的
D. 没有父母的
4. How many ways does the passage tell us to do if we want to help others? [ ]
A. One.
B. Two.
C. Three.
D. Four.
5. What's the best title of this passage? [ ]
A. Help those who need help.
B. It is not easy to help others.
C. How to be a happy person.
D. Donate your time.
（2）若把0.1 mol铁粉和1.6 g硫粉均匀混合后，铺在石棉网上用酒精灯加热引燃，完全反应后，将残渣全部放入过量的稀H2SO4中充分反应，结果所产生的气体体积在标准状况下明显少于2.24 L，其原因是__________________________________________________。