单项选择题A．They may crash because of nature disasters or human faults.B．The world’s weather conditions are getting worse.C．The airport safety inspections are getting worse.D．Airplanes are often overloaded nowadays.

单项选择题A．He may convert it and use it as a restaurant.B．He may pull it down and build a new restaurant.C．He may rent it out for use as a restaurant.D．He may sell it.

单项选择题A．Amy is seeking advice from Charlie about her future job.B．Amy is taking to Charlie about what she’d like to do in the future.C．Amy is discussing with Charlie what types of job she is suitable for.D．Amy is explaining to Charlie why some jobs are not suitable for her.

单项选择题A．bestB．leastC．mostD．worst

单项选择题A．fromB．toC．ofD．if

单项选择题A．raceB．paceC．speedD．step

单项选择题A．lastB．givenC．fixedD．definite

单项选择题A．spendingB．demandingC．consumingD．saving

单项选择题A．portionB．percentageC．proportionD．fraction

单项选择题A．BecauseB．WhileC．SinceD．When