证券交易所的组织形式及其比较？

Many people love going on a trip by plane, because planes are fast. But an airport(机场) is usually far away from the city, and it usually takes hours to get out of the airport and into the city. You have to get there and wait for the plane to take off for hours. You can not open the window, and you can not have delicious food.

I like travelling by train. I think trains are the safest(最安全的). Train stations are usually in cities. When you are late for a train, you can catch another one. You can walk around in the train and look out of the window. You can see many interesting things on your way. I know it takes some time.

I also like cars. You can start your trip when you want to, and you don’t need to get to a station. You can carry many things with you, too. But sometimes there are many cars on the road.

小题1:Many people like travelling by plane because_____________.

A．it is interesting

B．it is fast

C．it is cheap

D．it is expensive小题2:What does the underlined phrase “take off” mean?

A．Get to a place.

B．Fly away from a place.

C．Stop at a place.

D．Come back from a place.小题3:If you want to take many things with you, you can take___________.

A．a bus

B．a train

C．a car

D．a boat小题4:The writer thinks that ____________ are the safest.

A．trains

B．planes

C．boats

D．cars小题5:Which of the following is right?

A．Usually you need to spend hours getting out of an airport and getting into a city.

B．You can not see anything from a window when you are on a train.

C．A car never stops at a train station.

D．There are always too many cars on the road.

下述疾病除哪一种外均可发生在先天性中肠旋转不良的基础上（）

A.脐膨出

B.小肠扭转

C.盲肠后位阑尾

D.十二指肠梗阻

E.肠系膜动脉梗阻

Visitors to Britain may find the best place to sample local culture is in a traditional pub. But these friendly hostelries can be minefields of potential gaffes for the uninitiated.
An anthropologist and a team of researchers have (1) some of the arcane rituals of British pubs—starting with the (2) of getting a drink. Most pubs have no waiters—you (3) to go to the bar to buy drinks. A group of Italian youths (4) for 45 minutes before they realized they would have to (5) for their own. This may sound inconvenient, but there is a (6) purpose.
Pub culture is designed to (7) sociability in a society known for its reserve. Standing at the (8) for service allows you to chat with others (9) to be served. The bar counter is possibly the only (10) in the British Isles in which friendly conversation with (11) is considered entirely appropriate and really quite normal (12) . "If you haven’t been to a pub, you (13) been to Britain." This tip can be found in a (14) , Passport to the Pub: The Tourists’ Guide to Pub Etiquette, a (15) code of conduct for those wanting to sample "a central part of (16) life and culture". The trouble is that if you do not (17) the local rules, the experience may fall flat. For (18) , if you are in a big group, it is best if only one (19) two people go to buy the drinks. Nothing irritates the (20) customers and bar staff more than a gang of strangers blocking all access to the bar while they chat and dither about what to order.

图1所示液压系统可实现“快进-工进-快退-停止”的动作循环．要求列出其电磁铁动作循环表，并分析该液压系统有何特点？