is becoming, became, has become, aged, ages, age  Over the

is becoming, became, has become, aged, ages, age  Over the last fifteen years, running ______ a popular pastime for 30 million participants of all ______.
【正确答案】：has become, ages
【题目解析】：over加表时间的名词短语表示的是一段时间所以用完成体。各个年龄段的人用of all ages。