试题与答案

光线在均匀介质中按直线传播的特性称为()。A、直线传播定律 B、散射定律 C、折射定律D

题型:单项选择题

题目:

光线在均匀介质中按直线传播的特性称为()。

A、直线传播定律

B、散射定律

C、折射定律

D、泊松定律

答案:

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题型:阅读理解

One warm September night, Mira had come down to the beach to enjoy the night air. She closed her eyes and listened to the waves. Suddenly, she could hear another sound, so she opened her eyes and looked down at the sand. It was moving! All of a sudden she could see a tiny head coming out. Then a turtle(龟) appeared! One by one they struggled out of their underground nests. Mira looked in surprise at the baby turtles.

Mira knew the turtles should head towards the waves and swim away, so she was puzzled when they began to pull themselves towards the dunes(沙丘). Suddenly, she remembered something her grandmother had told her.

“Sea turtles bury their eggs on the beach every year in April and in September. Those baby turtles hatch(孵出) and head back down to the sea. But some of them never make it. Sometimes they die going across the dunes, trying to find those bright lights on the houses. Every day there are more houses being built on the dunes. That means more and more lights to confuse the sea turtles.”

Mira looked out across the dunes at her house. Mira saw her mother and father, sitting on the porch(门廊). She could see them because her house had two bright lights that lit up the porch.

Mira began to run to her house and shouted, “The turtles are hatching! We have to help the turtles!” With these words, Mira ran into the house and turned off the bright porch lights.

In a rush she was off running down the dunes with her whole family following her. They reached the beach just in time to see the tiny turtles slipping silently into the waves. Mira watched as the last turtle entered the water. As the turtle swam away, it looked back at Mira. In the moonlight, Mira thought she saw it smile.

小题1:Where did the story happen?

A.On a beach at night

B.In a house near the dunes.

C.On a front porch in the evening.

D.In the shallow water of the ocean.小题2:How did Mira feel when she saw the baby turtles appear?

A.Proud.

B.Sad.

C.Confused.

D.Surprised.小题3:How did Mira know the lights confused the turtles?

A.She read it in a book.

B.Her grandmother told her.

C.She learned about the turtles at school.

D.Her parents taught her about the turtles.小题4:Why did Mira run to her house?

A.To get a flashlight

B.To turn off the porch light.

C.To communicate with her parents.

D.To ask her grandmother about the lights.小题5:This story is mainly about a girl ________.

A.enjoying the ocean

B.turning lights off at night

C.saving the baby turtles

D.learning from her grandparents

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