【正文】 13．Yuan Longping is considered to have made a great _________ to the development of agriculture.A．progress B．invention C．introduction D．contribution14．When autumn es, the ________ will turn yellow, and fall from the tree.A．mountains B．leaves C．birds D．plants15．—I39。ll find it of great __________ in helping you.A．price B．cost C．interest D．value16．—The sweater is not the right ________ for me.—Well, shall I get you a bigger one or a smaller one?A．price B．color C．size D．material(材料)17．Yancheng Nature Reserve covers an ______ of over 45,000 square kilometers. It is one of the world’s most important wetlands.A．a(chǎn)rea B．object C．space D．population18．—Mr. Green, I can39。t worry! Why not try to make ___________ with them?A．decisions B．sentences C．suggestions D．choices19．The visitor told a very ______story about what he did for a ______in Africa.A．lively；living B．lively；life C．living；living D．a(chǎn)live； live20．The man next door is a ________ to Bruce. He doesn’t even know the neighbor’s name.A．stranger B．volunteer C．trainer D．teacher21．— I hear that you have bought a smart car. Does the car give you any good ________ for your money?— Certainly.A．value B．price C．wealth D．cost22．Cindy is always full of __________ because she takes a lot of exercise everyday.A．courage B．knowledge C．energy D．experience23．Kids under the age of ten can’t make good_______. They are not sure which is better for them.A．choices B．progress C．efforts D．mistakes24．Life is like riding a bicycle. To keep your ________, you must keep moving.A．promise B．position C．balance D．a(chǎn)bility25．With the development of the service industry, the working ________ is increasing and more jobs should be offered.A．invention B．pronunciation C．introduction D．population26．— Can you describe what Mr. Green’s daughter is like?— Oh, she has the very ______ of Mr. Green. I’m sure you can know her at the first sight.A．photo B．voice C．look D．taste27．—Do you know a Chinese called ChenGao?—Exactly, his ________ makes the whole world shocked and he bees the youngest PHD supervisor（博導(dǎo)）in Math area.A．a(chǎn)dvantage B．progress C．a(chǎn)chievement D．a(chǎn)ttention28．— Do you stay up at night and get up late in the morning just like me?— Never. I think you’d better break that_________.A．habit B．project C．a(chǎn)bility D．a(chǎn)dvice29．A ________ is a person who is travelling or visiting a place.A．stranger B．tourist C．guide D．customer30．The boy is crazy about football but he has no time to play it. He finds it difficult to keep ________ between his schoolwork and his hobbies.A．balance B．possibility C．relationship D．suggestion31．—Why are yo