下表反映了我国人均居住条件的变化，产生这一变化的主要原因是（    ）

If you want a____(永久的)job，you will have to be devoted to improving your skills.

   Everybody knows vegetables and fruit are g____for people．Many people eat some fruit each day．Mr and Mrs Smith like e____ fruit very much and every day Mrs Smith goes to buy some fruit in the shop near her home. She can buy all k____ of fruits there，such as apples，pears, oranges and bananas．In different time of the year the p____ of each kind of fruit is not the same，s____  high，sometimes low. Mrs Smith usually t____  to buy cheap fruit．And b____  are Mr Smith’s favourite fruit．Mrs Smith buys bananas for him every week．But she always chooses the cheap ones.“Eating fruit can help to keep f____ ，" said Mr Smith．“It's quite d ____ from snacks．Both of them can give us energy．But snacks l____ cakes, chocolates and sweets are not good for our health at all," 

材料一：“第一课”主讲老师王宁，从事汉语研究与教育工作长达六十余年，为了将传统文化巩固在每个中国人的血液中，王宁教授尽其所能，从未停止研究汉字。

材料二：主持人董卿在采访96岁的翻译家许渊冲先生时，以跪地的身姿，附耳提问，专注倾听。网友纷纷点赞这感人一幕。