下列是进行O２、CO２的实验室制取和有关性质的实验装置。
（1）写出带有序号仪器的名称：①_______________，②______________。
（2）用ＫMnO4固体制取O2，应选用上图中的_________装置（填字母），当Ｏ２收集满并取出集气瓶后，停止该实验的正确操作步骤是 。
（3）用稀盐酸和大理石在Ｂ装置中反应制取CO2并检验其有关性质，观察到烧杯中导管口有气泡冒出，但无其它明显现象。若证明CO2与NaOH溶液发生了化学反应，以下方案合理的是___________（填序号）。
① 取少量烧杯中液体滴加无色酚酞
② 取少量烧杯中液体滴加足量稀盐酸
③ 取少量烧杯中液体滴加足量石灰水
（4）用C装置制取了一瓶无色、无味的气体（纯净物），试用最简便的方法确定气体的成分 。
His younger sister may already be in high school now, in ________ case this picture book is too childish for her.
| A．that | B．which |
| C．whose | D．what |
It is by no means clear ________ the president can do something to end the strike.
| A．whether | B．which |
| C．that | D．what |
On a sunny day last August, Tim heard some shouting. Looking out to the sea carefully, he saw a couple of kids in a rowboat were being pulled out to sea.
Two 12yearold boys, Christian and Jack, rowed out a boat to search for a football.Once they'd rowed beyond the calm waters, a beach umbrella tied to the boat caught the wind and pulled the boat into open water.The pair panicked and tried to row back to shore.But they were no match for it and the boat was out of control.
Tim knew it would soon be swallowed by the waves.
“Everything went quiet in my head，” Tim recalls(回忆)．“I was trying to figure out how to swim to the boys in a straight line.”
Tim took off his clothes and jumped into the water.Every 500 yards or so, he raised his head to judge his progress.“At one point, I considered turning back，” he says.“I wondered if I was putting my life at risk.” After 30 minutes of struggling, he was close enough to yell to the boys, “Take down the umbrella！”
Christian made much effort to take down the umbrella.Then Tim was able to catch up and climb aboard the boat.He took over rowing, but the waves were almost too strong for him.
“Let's aim for the pier(码头)，” Jack said.Tim turned the boat toward it.Soon afterward, waves crashed over the boat, and it began to sink.“Can you guys swim？” he cried.“A little bit，” the boys said.
Once they were in the water, Tim decided it would be safer and faster for him to pull the boys toward the pier.Christian and Jack were wearing life jackets and floated on their backs.Tim swam toward land as water washed over the boys' faces.
“Are we almost there？” they asked again and again.“Yes，” Tim told them each time.
After 30 minutes, they reached the pier.Why did the two boys go to the sea?
| A．To go boat rowing. |
| B．To get back their football. |
| C．To swim in the open water. |
| D．To test the umbrella as a sail. |
What does “it” in Paragraph 2 refer to?
| A．The beach. | B．The water. |
| C．The boat. | D．The wind. |
Why did Tim raise his head regularly?
| A．To take in enough fresh air. |
| B．To consider turning back or not. |
| C．To check his distance from the boys. |
| D．To ask the boys to take down the umbrella. |
How did the two boys finally reach the pier?
| A．They were dragged to the pier by Tim. |
| B．They swam to the pier all by themselves. |
| C．They were washed to the pier by the waves. |
| D．They were carried to the pier by Tim on his back. |
I used to be a very selfcentered person, but in the past two years I have really changed.I have started to think about other people ____ I think about myself.I am happy that I am becoming a ____ person.
I think my ____ started when I was at Palomar College.At first, I just wanted to get my ____ and be left alone.I thought I was smarter than everyone else, so I hardly ever ____ to anyone in my classes.By the end of my first semester, I was really ____.It seemed as if everyone but me had made friends and was having fun.So I tried a(n) ___.I started asking people around me how they were doing, and if they were having trouble I ____ to help.That was really a big ____ for me.By the end of the year, I had several new friends, and two of ____ are still my best friends today.
A bigger cause of my new ____， however, came when I took a parttime job at Vista Nursing Home.One old lady there who had Alzheimer's disease became my ____.Every time I came into her room, she was so ____ because she thought I was her daughter.Her real daughter never ____ her, so I took her place.She let me ___ that making others feel good made me feel good too.When she died, I was ____， but I was also very grateful to her.
I think I am a much ____ person today than I used to be, and I hope I will not ____ these experiences.They have ____ me to care about other people more than about myself.I ____ who I am today, and I could not say that a few years ago.
A．since B．before C．or D．unless
A．famous B．simple C．different D．skilled
A．education B．career C．tour D．change
A．balance B．homework C．degree D．interest
A．talked B．wrote C．lied D．reported
A．careful B．lonely C．curious D．guilty
A．argument B．game C．experiment D．defence
A．dared B．offered C．hesitated D．happened
A．dream B．problem C．duty D．step
A．us B．which C．them D．whom
A．attitude B．hobby C．hope D．luck
A．friend B．partner C．guide D．guest
A．polite B．happy C．strange D．confident
A．bothered B．answered C．visited D．trusted
A．explain B．guess C．declare D．see
A．homeless B．heartbroken C．badtempered D．hopeless
A．quieter B．busier C．better D．richer
A．forget B．face C．improve D．analyze
A．forced B．preferred C．ordered D．taught
A．miss B．like C．wonder D．expect
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