完成句子（15分）
阅读下列各小题，根据括号内的汉语提示，用句末括号内的英语单词完成句子，并将答案写在答题卡上的相应题号后。
例：We     (起床)before dawn.It was still dark outside.(get)
答案：got up
71.Only if people of all the countries are united ________（我们才能解决）the existing problems in the world.(solve)
72. ________（油漆成）red,the building stands out among the rest and looks very attractive.(paint)
73. ________(不会用)a computer makes it more difficult for him to do his academic research.(use)
74.The news ________（房价将要下跌）has caused many people to sell their houses at lower prices.(fall)
75.After she completes the project,she’ll have ________（没什么要担心的）.(worry)
76.Mr.Johnson insisted that the problem worthy of attention ________(讨论)at the meeting.(discuss)
77.My mother was so proud of all ________（我所做的）that she rewarded me with a trip to Beijing.(do)
78.Last night’s TV news said that by then the death of the missing people ________（未证实）yet.(prove)
79.It’s said that they have swum to the island from the continent,but they ________（不可能做到）because the ocean in between is too wide.(do)
80. ________(正如我们强调的那样)many times,“serve the people”is our first policy.(stress)