问题 选择题

下列实验现象叙述错误的是(  )

A.木炭放入氧气中可以生成二氧化碳

B.铁在氧气中燃烧时火星四射

C.镁在空气中燃烧发出耀眼的白光

D.氢气在空气中燃烧,发出的淡蓝色火焰

答案

A、木炭在氧气中燃烧后,能生成无色、无味的气体,不能说生成二氧化碳,描述现象时不能出现生成物的名称,故选项叙述错误.

B、铁在氧气中燃烧火星四射生成黑色固体.故选项正确.

C、镁条在空气中燃烧,发出耀眼的白光,生成一种白色固体;故现象描述正确.

D、氢气在空气中燃烧,发出淡蓝色火焰,选项说法正确.

故选A

阅读理解

Flight cancellations(取消) and loss of luggage can ruin even the best-planned holiday. The key to a stress-free trip is having a backup plan.

Fly non-stop. The worst problems involve connections, so it is important to take non-stop flights whenever possible. If you do have to make a connection, try to route through a southern city, where snowstorms and de-icing delays will be less likely. Always allow at least two to three hours for flight connections.

Check the weather. Check the weather in your connecting city, not just the arrival and departure city. If your departure flight is cancelled because of weather, you can go home or back to your hotel. Airlines promise to get you on the next available flight, not the next flight. That could be several days later on a sold-out holiday weekend.

Go early. The earlier in the day you fly, the better your chance of getting rebooked the same day after a missed connection. It will also put you ahead of stranded(滞留的) passengers who arrive later.

Rebook immediately. As soon as your flight is delayed or cancelled, get on the phone and rebook your flight instead of waiting at the ticket counter. If your rebooking is delayed, call or ask your travel agent to find a seat on another carrier, and then ask your original carrier to endorse your ticket to the new airline. Airlines are not required to do this but often do. Learn more at www. dot. gov/ airconsumer/ fly-rights.

Ship bags. A few days before your flight, ship suitcases or holiday gifts to your destination by a documented express service. It’s preferable to losing bags because of re-routed flights and sometimes cheaper than paying airline overweight bag fees.

Know your rights. Airlines are not required to compensate passengers for delayed or cancelled flights, but it never hurts to ask for goodwill vouchers(折扣) for meals, taxis or a room.

小题1:When making a flight connection, it’s common that you’ll___________.

A.stop in the south

B.choose a good city without snowstorm

C.be trapped in the storm

D.wait for two or three hours小题2:The suggested way for you to rebook your flight is___________.

A.through the phone

B.by waiting at the ticket counter

C.by changing another airline

D.by surfing the Internet小题3:According to the passage, we can infer____________.

A.it will take long to rebook the tickets

B.your luggage is easy to be lost

C.you will pay more for your overweight luggage

D.with the same ticket you can take the next flight小题4:The underlined word “compensate” in the last paragraph can be replaced by “___________”.

A.pay

B.ask

C.host

D.treat小题5:What’s the best title of the passage?

A.The Worst Problem in the Trip.

B.The Preparation Before the Flight Trip.

C.How to Book the Plane Ticket.

D.How to Plan the Holiday.

名词解释