WHY IS THE SUN  IMPORTANT？
The sun is a huge, hot, bright star. It is important because without it there would be no life on Earth. The sun gives us light and heat.
All living things need light and heat from the sun to live. Plants need light and heat to grow. They use the light from the sun to make food. We cannot make our own food, but plants can. All the food we eat comes from plants in a food chain(链)which starts with the sun. For example,

Animals need sunlight, too. Just like us, their food comes from a food chain which begins with the sun and the plants.
sun→ leaf→ caterpillar(毛虫)→bird
sun→ seaweed(海藻)→small fish→ whale(鲸)
Sunlight means we can see during the day. If there was no sun, it would be dark all the time. Even when the sky is cloudy, the sunlight is very strong and it shines through the clouds.
The sun is a           star.
A. huge, cold and bright
B. huge, hot and bright
C. small, warm and bright
What are the two main things the sun gives us?
A. Light and heat.
B. Heat and eggs.
C. Corn and light.
From the passage we learn that         .
A. when the sky is cloudy, there is no sunlight at all
B. without the sun there will be no life on the earth
C. we human beings can make food by our own bodies
All the food we eat comes from          in a food chain. And the food chain stars with the        .
A. plants; earth
B. plants; sun
C. animals; star
Which is the best title (标题) for this passage?
A. Plants need heat and light to grow
B. All living things depend on the sun for their growth
C. The sun is very important