题目

廊桥是我国古老的文化遗产．如图，是某座抛物线型的廊桥示意图，已知抛物线的函数表达式为，为保护廊桥的安全，在该抛物线上距水面高为8米的点、处要安装两盏警示灯，则这两盏灯的水平距离是     （精确到1米） 答案：解析:略用括号内所给动词的适当形式填空。【1】To celebrate the wedding, Nick says he’ll have his house ____________(paint).【2】— How was your trip to Hong Kong?— It couldn’t be worse. We ____________(keep) at the airport for at least 5 hours.【3】Jenny ____________(chat) with her friends, so I just nodded to her and went away.【4】Young people keep their hands on the phone whenever they go, even while they ____________(eat).【5】Well, that’s the best way I could think of ____________(reach) an agreement with the customers.【6】When the wind of change ____________(blow) some build walls, while others build windmills(风车).