My name is Cheng Ao．I____from Shanghai，a big city in China．I'm thirteen____old and I'm in Class 2．Miss Liang's class．Miss Liang is my____teacher．

    I have a small family：my parents____I．My father is a Chinese teacher in a big school．My mother is a hotel manager．They like to play basketball with me____Saturday．

已知抛物线的顶点坐标为M（1，-2），且经过点N（2，3），求此二次函数的解析式．

元素在自然界里分布并不均匀，如智利富藏铜矿，澳大利亚多铁矿，山东的黄金储量居我国首位，但从整个的地壳含量的多少分析，最丰富的金属元素是   （   ）

The Greens ________live in the south of Asia . They don't want to move to the north because they ________ the cold weather.

保护生物多样性的根本措施是（  ）