7． The experiment shows that proper amounts of exercise, if regularly, can improve our health. A．being carried out B．carrying out C．carried out D．to carry out 答案:C 考点:本题考查if条件句中的省略情况. 解析:本句的句子的主语是the experiment,谓语动词是shows,that引导宾语从句.宾语 从句的主干事:proper amounts of exercise can improve our health.if regularly是插入 的条件从句.从句的主语是proper amounts of exercise.此时应用it代替前面提到的主语. 条件句的主语与主句的主语一致.并且含有is.故省略了it is.完整形式是:if it is carried out.句意为:这项实验表明.适当的运动.如果有规律的进行.能够有助于我们的身体健康. 2009年高考题 【查看更多】
