Ⅲ.补全句子

　　1．It's_up_to_you_to_decide (由你来决定) who is up to the job.

　　2．We suggest that they (should)_speed_up (加快) the pace of their educational and economic reform.

　　3．You need a break. Why_not_(为何不) take a fortnight off from work?

　　4．They undertook_to_promote (同意促进) exchanges and trade.

　　5．Many diseases arise_from (由......引起) water pollution.

　　6．He undertook to pick me up, but he didn't turn_up (出现) until 9 o'clock.

　　[话题语篇高考练]

　　Ⅳ.阅读理解

　　A

　　When Taking an Uber - Should You Tip or Not?

　　Taking an Uber car may no longer be a direct driver­passenger and guilt­free experience. The ride­sharing experience is about to get awkward.

　　With the wide application of the Internet, Uber, a new approach to your destination instead of taking an ordinary taxi, has become more and more popular recently. However, benefits won't come without its fair share of drawbacks.

　　Uber drivers are a part of the so­called sharing economy: They use their own vehicles, receive customer reviews via the app's five­star rating system and make their own hours. Unlike other services, Uber claimed that drivers all over the country could clearly alert customers that tipping is not included. Those drivers that expect to be tipped can make their wishes known. But the company is holding to its official no­tip­required line, according to its website. "Once you arrive at your destination, your fare is automatically charged to your credit card on file - there's no need to tip." Although drivers value their independence - the freedom to push a button rather than punch a clock, lack of a clear policy, however, leaves Uber drivers in a vulnerable (易受责难的) position: If they ask a customer for a tip or put up a sign, that customer could give the driver a low star­rating, and the driver could finally be deactivated from the app.

　　But has the company done a good job working with customers? Some observers say that this new gray area for tipping will create awkwardness about whether they should tip or not - something most Uber customers have not had to deal with until now. Uber did not respond to customers' comment, just leaving their rating in the air.

Providing an option to tip on an app sends a clear message to customers to reach into their pockets. Nearly 30% people would be more likely to leave a tip if they were presented with a "no tip" button, according to Guinn's 2015 survey of roughly 500 people. When