阅读下面材料，在空白处填入适当的内容（1个单词）或括号内单词-优题课

A little boy invited his mother (attend) his elementary（初级的） school’s first teacher-parent meeting. To the little boy’s ________________(happy), she said she would go. This would be the first time that his classmates and teacher met his mother and he was embarrassed by her appearance. she was a beautiful woman, there was a severe scar（伤痕）_____________covered nearly the whole right side of her face. The boy never wanted to talk about why or how she got the scar.
At the meeting, the people were impressed by the kindness and natural beauty of his mother though she had a scar on her face, but the little boy was still embarrassed and _______________ (hide) himself from everyone. He did, however, get within earshot of（在听力范围之内） a conversation _______________ his mother and his teacher, and heard them speaking.
‘‘How did you get the scar on your face? ’’ The teacher asked.
The mother replied, ‘‘When my son was a baby, he was in a room that caught on fire. Everyone was too afraid to go in the fire was out of control, so I went in. As I was rushing toward his bed, I saw a beam(房梁) coming down and I placed myself over him trying to protect him. I was knocked unconscious(无意识的) but _______________ (fortunate), a fireman came in and saved both of us.’’ She touched the burned side of her face. ‘‘This scar will be on my face for ever, but to this day, I have never regretted doing _______________I did.’’
At this point, the little boy came out , _______________(run) towards his mother with tears in his eyes. He hugged her and felt a great sense of the sacrifice that his mother had made for him. He held her hand tightly for the rest of the day.

A young American woman worked in a school in Shanghai．she came to China，she knew little about the Chinese culture of language． One day on her way to school，she went to a bank (draw) some money．To surprise，the bank clerk(职员) asked her if she had had her lunch．She was surprised at such question because in the American culture it would mean that the bank clerk is inviting her to lunch．Between unmarried young people it can also mean the young man’s interest in dating the girl．Since this bank clerk (be) a stranger to the American woman，she was very puzzled(困惑的)，and quickly answered that she had (eat) already．After this she went on to school and was even surprised when one of the teachers asked her the same question．
By now she understood that it could not be an (invite) but was puzzled as to why they asked it．In the following days she was asked the same question again and again and she spent many hours (try) to work out why so many people kept asking her this．At last she thought that these people must be (concern) about her health．She was rather thin at the time，and she thought they must be worrying that she was not eating well!
In fact the question like that has no real meaning at all — it is only a greeting．

A young man and an old man were waiting for a bus. sat next to each other. “What’s that in your bag?” asked the young man, pointing to a big bag beside the old man.
“Gold. There was nothing but gold,” answered the old man. The young man could not believe his own ears and was great surprise. Then he began to think about to get the money. The old man was very tired and it seemed that he could hardly keep his eyes open. After a while the old man (lie) down on the chair and fell asleep.
The young man took big bag gently and quietly. But when he was just about to run away, he found a corner of his fur coat was under the old man’s body. Several times he tried to pull it out, in vain（徒劳）. At last he took off his coat,(think) that the gold in the bag must cost far more than his fur coat.
Worried but (delight), the young man ran out of the station as quickly as his legs could carry him, until he reached a place he thought the old man couldn’t find him. He stopped and (quick) opened the bag but he just found a great many of small stones in it. Then he ran back to the station hurriedly only to find that the old man was gone.

Polar bears are suffering in a(warm) world than ever before.
Polar bears live in environments too cold for most animals. For much of the year,live and hunt on the frozen Arctic sea ice. Nature has prepared them for the cold conditions. But nothing has prepared the bears for the danger threatening the only homethey know.
The polar bears’ world is melting. Studies show that the polar ice(reduce) by 9.8% every 10 years since 1978. Now about 20,000 to 25,000 polar bears live in the Arctic. Polar bears depend on the sea ice for their(survive). “The sea ice is more than just this platform that the bears walk over.” says Andrew Derocher,scientist who studies North American polar bear populations. “it, they can’t exist.”
Some melting and refreezing of the polar ice is natural. in a warmer world, these cycles speed up, and bears have less time(hunt). Normally, they have three months in the spring when they gain more weight. The extra fat is used later, the bears are not actively hunting.

Rivers are one of our most important natural resources. Many of the world’s great cities are ______ (locate) on rivers, and almost _______ country has at least one river flowing through it that plays ________ important part in the lives of its people.
Since the beginning of history, people _______ (use) rivers for transportation. The longest one in the United States is the Mississippi, and the lifeline of Egypt is the Nile. _________ transportation, rivers give water to drink, water for crops, and chances for fun and recreation for the people ______ live along their banks.
However, large cities and industries that are located on rivers often make problems. As the cities grow _______ size and industries increase in number, the water in the rivers becomes ________ (pollute) with chemicals and other materials. People are learning the _________ (important) of doing more to keep their rivers clean ________ they want to enjoy the benefits of this natural resource.