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A biologist is a kind of scientist who studies living things. Some biologists study plants and other biologists study animals. They help us learn about life in our world.
Some biologists work in labs while others work outdoors studying animals and plants. This is called field work. Some biologists even help save forests or study sea animals.
Biologists need to learn how to solve problems. They want to know more about living things.
Word List
lab : a special room for doing science work
field work doing science work outside of a lab
You Practice
I. Complete the sentences with words from the reading.
1） A b _ _ _ _ _ _ _ _ is a scientist who studies living things.
2） Some biologists work outside. This is called f _ _ _ _ w _ _ _.
3） Some biologists work in a room called a l _ _.
4） Some biologists work to save f _ _ _ _ _ _ or study sea animals.
II. What's the word? Using the clues, write the correct words from the reading.
1） This is a place with many trees: f _ _ _ _ _
2） These can live in forests or oceans: a _ _ _ _ _ _
3） This is to learn more about something: s _ _ _ _
4） This area is not indoors: o _ _ _ _ _ _ _
III. Answer the following questions.
1） What does a biologist do?
2） Where do biologists work?
3） Would you like to be a biologist? Why or why not?
I. Fill in the blanks. Choose the correct words from lessons 1− 4 to complete the sentences.
1） Some scientists do f _ _ _ _ w _ _ _. They work outside.
2） An animal's h _ _ _ legs are at the back.
3） A room where some scientists work is called a l _ _.
4） Snakes have v _ _ _ _ in their teeth.
5） A c _ _ _ _ is many things together.
II. Answer the following questions.
1） What are some creatures that you like?
2） What are some features that animals use to survive?
3） Would you like to do field work or work in a lab? Why
4） What are some animals that are usually the prey of other animals?
5） Where can we find embryos
III. Read each sentence carefully. Write Yes or No.
____ 1） Plants inject venom into their prey.
____ 2） A clump of things is more than three.
____ 3） People have hind legs.
____ 4） Different animals have different features.
____ 5） An embryo is very large.
IV. Draw a picture of a creature that has hind legs. What is it?
This is a ___________. It has hind legs.
Soil is the top layer of much of the Earth's land surface. It is a mixture of broken rock, humus — bits of dead plants and animal waste — air, and water. Different kinds of soil have different sizes of rock particles and can be found in various places.
Soil is lost when it is blown by wind or carried away by rain or rivers. Mountain soil is gradually lost due to gravity if the trees that hold it are logged. This is called soil erosion. It can be prevented by keeping trees healthy.
Word List
waste : material that comes out of animals after they eat
gradually : slowly
gravity : the force that pulls objects down to Earth
particles : very small pieces
logged : when trees are cut down
prevented : stopped
You Practice
I. Answer the following questions.
1） What is soil made from?
2） How is soil lost?
3） How can soil erosion be prevented?
4） How is soil different in various places?
II. Read the sentences carefully. Write Yes or No for each one.
____ 1） Cutting down trees is good for soil.
____ 2） Soil is sometimes carried away by rivers.
____ 3） There is no way to stop soil erosion.
____ 4） Soil is the bottom layer of the Earth's surface.
____ 5） There are dead plants in soil.
III. What's the word? Using the clues, write the correct words from the reading.
1） This includes dead plants, broken rock, air, water, and animal waste: h _ _ _ _
2） This is at the top: s _ _ _ _ _ _
3） These are very small pieces: p _ _ _ _ _ _ _ _
4） This means slowly, not quickly: g _ _ _ _ _ _ _ _
5） This is when trees are cut down: l _ _ _ _ _