理想变量器电路中，若初、次级匝数比为N，初级电流为i1，初级电流为i2，则下式正确的

完形填空。（每小题2分，共20分）
根据短文内容，从A、B、C、D 四个选项中选出一个能正确填入相应空格内的最佳答案，并把答题卡上对应题目的答案标号涂黑。
Why do we take school trips? School trips are a great chance to learn outside the classroom      41      new and interesting ways. For example, on a trip to a farm, we can see   42          of the things we        43     about so far in biology lessons. While   44       science
museums, we can see science in action.
Where can we go on a school trip? In Japan, cherry (樱花) trees are blossoming (开花) by the beginning of the year for students to take school trips. School children have picnic lunches, sing songs and dance under the trees. They       45    go boating and hiking around the lakes and hills. Some kids even take baths in hot springs. If there is     46     , don’t worry. They will go to a museum     47     .
In China, students often take school   48     to parks, museums or to visit a mountain. But nowadays it’s very popular to take an outward bound(野外拓展) trip.  Students can learn about survival skills.(生存技能)
In the UK, students go to many interesting places. They     49     shells(贝壳) on the seaside . Kids may also learn about      50        when they go to a castle(城堡) or a famous old home.
小题1:.

A．by

B．with

C．in

D．on

小题2:	A．every B．both C．none D．some

小题3:	A．learn B．learned C．have learned D．is learning

小题4:	A．visiting B．visit C．traveling D．travel

小题5:	A．like B．too C．also D．would

小题6:	A．rainy B．rains C．raining D．rain

小题7:	A．instead B．instead of C．rather than D．rather

小题8:	A．meetings B．trips C．lunches D．classes

小题9:	A．pick up B．bring C．carry D．put down

小题10:

A．music B．math C．biology D．history