问题 选择题

锋面形成或加强的过程叫锋生,锋面消失或减弱的过程叫锋消。下图中T1、T2、T3为等温线,t1、t2、t3为气流辐合、辐散过程中的三个时刻,回答下列各题。

小题1:下列叙述正确的是(   )

A.图中气温梯度为t1>t2>t3

B.图中沿虚线方向表示气流辐合过程

C.图中沿实线方向表示锋消现象

D.水平温度梯度变大是锋生的主要标志小题2:我国大部分地区处于温带,冷、暖气团活动频繁,锋生现象十分明显,下列地区中属于主锋生地带的是(  )

A.四川盆地

B.西北地区

C.东北—内蒙古一带

D.青藏地区

答案

小题1:D

小题1:C

本题考查天气系统和读图分析能力。

小题1:t1、t2、t3三个阶段,等温线越密集,气温的梯度越大,由此可以判断t3>t2>t1;图中气温梯度变大,表示的是锋生过程,而气温梯度变小,表示锋消的过程;因此D选项正确。

小题2:我国在东北-内蒙古一带,由于纬度高,靠近冬季风的源地,再加上地形的影响,是冷空气聚集地区,也是主锋生地带。

阅读理解

A long time ago, there was a seed and because he was only a seed, nobody noticed him.Thus, feeling inferior (低等的), the seed gave no importance to his existence (存在).

Then one day, a wind picked him up and threw him on an open field under the sun.Later, he was given rain.

Years later he saw a traveler sitting by his side.“Thank God for this.I really need some rest,” he heard the traveler say.

“What are you talking about?” the seed quickly asked.He thought the man was making fun of him.No one ever spoke to him like that.

“Who just spoke?” the shocked man asked.

“It is me.A seed.”

`“A seed?” The man looked at the big tree.“Are you joking? You are not a seed.You are a big tree!”

“Really?”

“Yes! Why else do you think people come here?”

“What do they come here for?”

“To feel your shade (树荫)! Don’t tell me you didn’t know you had grown over time.”

A moment passed before the traveler’s words brought him pride.

The seed thought and smiled for the first time in his life.The years of torture (折磨) by the sun and the rain finally helped him grow up.

“Oh! That means I’m not a little seed anymore! I was actually born to make people feel comfortable.Wow! That’s great!”

小题1:The seed didn’t realize the importance of his existence because ______.

A.nobody looked after him

B.he was thrown into the open air

C.he was such a small seed

D.he didn’t believe in himself小题2:The traveler sat by the seed’s side to ______.

A.escape from the rain

B.thank God for offering him a tree

C.have a rest and enjoy the shade

D.talk with the big tree小题3:The author’s purpose of writing the passage is to ______.

A.tell us that we should help each other

B.praise the seed for his strength

C.teach us not to laugh at others

D.tell us never to lose hope小题4:Where does the passage most probably come from?

A.A history book.

B.A science book.

C.A storybook.

D.A novel.

单项选择题