建筑幕墙后置埋件应进行承载力现场试验，必要时应进行()试验。A.极限抗弯 B.极限抗

右图是巴斯德著名的“鹅颈瓶”实验示意图．A瓶、B瓶内都装有肉汤，甲图表示A瓶煮沸，B瓶不作处理．一段时间后，其中一瓶仍然保鲜，另一瓶变质；接着，将保鲜那瓶的瓶颈打断（如乙图），数日后，瓶中肉汤也变质了．请回答：

（1）甲图中肉汤仍然保鲜的是A瓶，而将其瓶颈打断后肉汤变质的原因是空气中的______进入瓶内．

（2）甲、乙两组实验所控制的变量都是______．

A．瓶子的大小；B．细菌的有无；C．肉汤的多少

乙图中控制该变量的方法是将瓶颈打断；而甲图中控制变量的方法则是______．

（3）这个实验证实了细菌______．

A．是自然发生的；B．是由原已存在的细菌产生的．

He was struggling to tie his shoes. I was struggling with whether I should help him.
I did, and he was grateful.
"Thank you," he said.
"I’m glad I could help. I just thought it would be easier for me to reach," I said.
He was a disabled man, and forced to look down most of the time. His arms and legs were twisted terribly, and he couldn’t do what the rest of us would consider easy tasks. He always managed to Look up to see how you reacted to his words, however. He had a big smile, making me feel comfort- able.
I was still on my knees by his wheelchair.
"Nice shoes," he said.
"Thanks. No one ever complimented me on them before," I said.
"No one has the same view of the world as I do," he replied.
"Tell me about the world as you see it," I said smiling.
"Most people can see if someone is comfortable with them or not in their eyes. I see it in their feet," he said. "If people keep moving their feet, I just let them go, because I know they’re impatient with me. I don’t want to make people uncomfortable."
"What about me" I asked.
"I could see your compassion. And then you came down to my level. I was the one who was nervous," he said. "I don’t normally have someone look me in the eye. "
"They don’t know what they’re missing," I told him.
"My old face is nothing to brag about. " he said.
"But that smile is so big. "
Yes, and it’s not only a big smile but an attitude.

We can infer from the passage that ______.

A．the disabled man had something wrong with his mind

B．not many people went down to the man’s level

C．the man was good at telling people about the world

D．the writer would not give the man more help

在中外交往过程中，唐朝首都( )成为国际性大都会。

A．长安

B．河西

C．江西

D．汴京

简评闻一多在新诗发展史上的地位。

包装技术中常用的驱虫剂有（）。

A.荼

B.对位二氯化苯

C.樟脑精

D.氧化钠

E.二氧化碳