题干

席夫碱类化合物G在催化、药物、新材料等方面有广泛应用.合成G的一种路线如下:

已知以下信息:

②1molB经上述反应可生成2molC,且C不能发生银镜反应.

③D属于单取代基芳烃,其相对分子质量为106

④F苯环上的一氯代物有2种

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      With the summer holiday just around the corner, it seems like everybody is busy planning their vacations. Here are some tips that can helpyou enjoy your holiday without emptying your pocket:

Travel off-season

      Go to your desired destination while the demand is low and takeadvantage of huge discounts. During the peak season, the hotel and flightprices increase quickly, and you’ll likely spend more of your vacation timestanding in line due to the rush of tourists.____

____

      Websites can help you find discount hotel rooms. Look for placesthat do not charge extra for children if they use the existing bedding. Staywith the locals. If you and your family are going to stay for a longer period,renting a small apartment is a good choice.

Eat like a local

      Why eat at big chain restaurants when you can experiencesomething new?____

During your family trip, try new food where the locals eat. Thiswill not just save money, but also provide you with a new and differentexperience. For smaller meals and snacks, avoid restaurants and try street foodor other takeout.

Don’t hesitate to bargain

      Tourist- heavy places are known for overcharging for just abouteverything. Clothes, travel goodies, souvenirs, etc. are very expensive atthese places. ____ Bargain hard to get the best price.

Choose local transportation

____

      Instead, take buses, railways or subways, which are alwayscheaper. If you are planning to stay for a while, you can consider renting acar. Hiring a car is much easier than carrying your bags everywhere if you aremoving around a lot.

A. Save on hotels.

B. Surf the Internet while traveling.

C. Therefore, avoid buying anything there.

D. So it’s best to find out when the off-season starts.

E. Planning your meals is another way to reduce your travelcosts.

F. For this reason, you shouldn’t feel ashamed to ask forbargains.

G .As a tourist, avoid taking taxis whenever possible, sincethey are expensive.