Dollars and cents are the basic units of American money. The back of all dollar bills are green (hence "greenbacks"). The commonly used coins are one cent (penny) ,five cents ( nickel), 10 cents(dime),and 25 cents (quarter), 50 cents (half dollar) and silver dollars (not really silver anymore) are gaining in usage, while there has been talk of phasing out the penny that’s inflation for you. "Always carry plenty of quarters when traveling. Very useful for phones, soda machines, laundry machines, etc."
There is generally no problem in using US dollars in Canada, but this is never possible in reverse.
It’s useful always to carry small change for things like exact fare buses, but do not carry large sums of cash. Instead keep the bulk of your money in travelers’ checks which can be purchased both in the US and abroad and should be in dollar denominations. The best known checks are those of American Express, so you will have the least difficulty cashing there, even in out of the way places. Thomas Cook travelers’ checks are also acceptable, especially as lost ones can be reclaimed at some car rental companies. Dollar denomination checks can be used like regular money. There’s no need to cash them at a bank: use them instead to pay for meals, supermarket purchases or whatever. Ten or twenty dollar checks are accepted like this almost always and you’ll be given change just as though you’d presented the cashier with dollar bills. Be prepared to show I.D. when you cash your checks.
Credit cards can be even more valuable than travelers’ checks, as they are often used to guarantee room reservations over the phone and are accepted in lieu of deposit when renting a car—indeed without a credit card you may be considered so untrustworthy that not only a deposit but your passport will be held as security too. The major credit cards are VISA, Master Charge and Access, Diners Club and American Express. If you hold a bank card, it could well be worthwhile to increase your credit limit for travel purposes—you should ask your bank manager.
It is not necessary to carry cash instead of travelers’ checks because the latter can be ______.

A．three months
B．two months
C．five months
D．six months

At 16 students in England and Wales take GCSE examinations. These examinations are taken by students of all levels of ability in any of a range of subjects and may involve a final examination ,an assessment of work done during the two-year course, or both of these things. At 18 some students taking A-level examinations, usually in not more than 3 subjects. It is necessary to have A-levels in order to go to a university or polytechnic.
In Scotland students take the SCE examinations. A year later, they can take examinations called HIGHERS, after which they can either go straight to a university or spend a further year at school and take the Certificate of Sixth Year Studies. In Scotland the university system is different to that in England and Wales. Courses usually last four years rather than three and students study a larger number of subjects as part of their degree.
In the US school examinations are not as important as they are in Britain. Students in High Schools do have exams at the end of their last two years, but these final exams are considered along with the work that the students have done during the school years.
Social events and ceremonies
In American high schools there is a formal ceremony for Graduation. Students wear a special cap and gown and receive a diploma from the head of the school. Students often buy a class ring to wear, and a yearbook, containing pictures of their friends and teachers. There are also special social events at American schools. Sports events are popular, and cheer leaders lead the school in supporting the school team and singing the school song. At the end of their junior year, at age 17 or 18,students hold parties in the evening. The girls wear long evening dresses and the boys wear tuxedos(晚礼服).
In Britain, there are no formal dances or social occasions associated with school life. Some schools have SPEECH DAY at the end of the school year when prizes are given to the best students and speeches are made by the head teacher and sometimes an invited guest. However, in many British schools students and teachers organize informal dances for the older students.