1.keep＋宾语＋宾补 Water helps . 水有利于保持你的身体内部系统清洁。 2.so＋be动词/助动词/情态动词＋主语 Walking and riding your bike count，and . 步行和骑自行车就算，校内体育活动也算。

Ⅲ.重点句式

keep your system clean

so do school sports