请你对下文内容进行修改。文章中共有10处错误，每句中最多有两处。错误涉及一个单词的增加、删除或修改。

增加：在缺词处加一个漏词符号（∧），并在此符号下面写出该加的词

删除：把多余的词用斜线（﹨）划掉

修改：在错的词下划一横线，并在该词下写出修改后的词

注意： 1.每处错误及其修改均仅限一词

2．只允许修改10处,多者(从第11处起)不计分

My favorite sport is football. I was a member of our school football team. We practice for three times every week and often watch football match on TV together. Play football not only makes us grow up tall and strong but alsogive us a sense of fair play and team spirit. We must keep in minds that we play for the team instead ourselves. Also sport teaches us the important of obedience (服从) . Each player must obey the captain, which is the leader of the team. And they must not break the rules too often if we want to win the game.

对于外加剂混凝土含气量测定仪的振动时间，正确的是（）。

A、振动时间长，结果偏大

B、振动时间长，结果偏小

C、振动时间短，结果偏小

D、振动时间长短对结果没有影响