How Do Eyes See? | A2 ESL Science Reading Passage

Use this A2-B1 ESL science reading passage to learn how eyes see. It includes key vocabulary, reading comprehension questions, and answers for English learners.

Eyes see when light enters the eye and signals travel to the brain.

Reading Level

A2-B1

Word Count

186 words

Reading Passage

Seeing begins with light. We can see a book, a tree, or a friend's face because light reaches our eyes. Without light, the eyes cannot make a clear picture.

Light first enters the eye through the pupil. The pupil can become larger or smaller. In a dark room, it becomes larger to let in more light. In bright sunlight, it becomes smaller to protect the eye.

After light enters the pupil, it passes through the lens. The lens bends the light and helps make a clear image. This is a little like the lens in a camera.

At the back of the eye is the retina. The retina has special cells that notice light and color. These cells change light into signals.

The signals travel from the eye to the brain through a nerve. The brain reads the signals and understands them as pictures. This is how we know the shape, color, and movement of things around us.

The eyes and brain work together very quickly. You do not have to think about each step. Light enters, the eye sends signals, and the brain helps you see the world.

Light enters the pupil, passes through the lens, reaches the retina, and becomes signals for the brain.

Key Vocabulary

Word	Meaning	Example
pupil	the dark opening in the center of the eye	Light enters through the pupil.
lens	a clear part of the eye that helps focus light	The lens bends light.
retina	the back part of the eye that senses light	The retina changes light into signals.
signal	a message sent inside the body	Signals travel to the brain.
image	a picture or shape that we see	The brain understands the image.

Reading Comprehension Questions

1. What does seeing begin with?
2. What part of the eye does light enter first?
3. What does the lens help do?
4. What does the retina change light into?
5. What reads the signals from the eye?

Answers

1. Seeing begins with light.
2. Light first enters through the pupil.
3. The lens helps focus light and make a clear image.
4. The retina changes light into signals.
5. The brain reads the signals from the eye.

Short Summary

Eyes see when light enters through the pupil, passes through the lens, and reaches the retina. The retina sends signals to the brain, and the brain understands them as pictures.

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