学进去

阅读下面短文，从各题所给的A、B、C三个选项中选出最佳选项，并将选项番号填入答题卡上对应题号后面的括号内。

Humans spend about one third of their lives sleeping. We could have used the time to do more important things like eating, looking after our families and working. Some scientists believe sleeping helps recharge(恢复精力) the body. But now a study suggests that we sleep to forget some of the millions of new things we learn each day. Sleeping can help people forget unimportant information.

The research explained that there are dendrites (树状突) in the human brain. They grow and connect at synapses (突触). This is how we learn new things. The larger the dendrites grow and the more synapses we have, the more information we remember. Researchers said that we learn so many things each day that the dendrites grow too large and we become confused (迷惑的). Sleeping helps the dendrites become smaller. We clear out the unimportant information and only keep the most important memories.

The team did an experiment on two groups of mice over a four-year period. One group of mice could sleep, while the other group was kept mostly awake. The team found that the sleeping mice had nearly 20 percent fewer synapses.

Most researchers believe clearing our brains is not the only purpose of sleep. Resting our minds and bodies can stop us getting sick and help digest (消化) food. There is one thing scientists all agree on: a good night’s rest is important for our health and happiness!

1．This article is probably from a “________” section in the newspaper.

A．reading fun

B．science study

C．school time

2．Common people spend one third of their lives ________.

A．sleeping

B．eating

C．caring for their families

3．The new study suggests that people sleep to ________.

A．recharge their bodies

B．forget unimportant things

C．rest their minds and bodies

4．The experiment on mice showed the sleeping mice ________.

A．had about one fifth fewer synapses

B．had their dendrites grow larger

C．got more synapses and remembered more

5．All scientists agree that sleeping ________.

A．can help us to digest food

B．can help us to remember more clearly

C．is key to our health and happiness