Ithinksummerismyfavotiteseason.

　　first,insummerwedonothavetowearalotofclothes,girlscanweartheirkindsofbeautifulskirtsandboyscanweart-shirt.

　　second,insummeryoucandoalotofsportssuchasfootball,basektball,pingpang,ofcause,swimmingismyfavoritesport.

　　atlast,therearesomanydeliciousinsummer,kindsofice-reamandfruit,barbecue,beerandsoon.

　　asaword,Ithinkyoucandotoomanythingstomakeyouselffeelrelaxandenjoyyouself,so,summerismyfavoriteseason!

　　水平有限,如果是高中作文的话,这个语法上基本OK!参考下吧