应援是指应援活动

是一种支持行为

应援可以说support activities

粉丝应援可以说

support by fans

句例：

一份报告显示，1280万18岁以下的互联网用户经常参与明星应援活动。

A report shows that 12.8m internet users under 18 frequently engaged in“fan-support” activities.

禁止义务教育阶段未成年人参加偶像团组和线下应援活动。

They should be forbidden from joining “idol” groups and offline support activities.

中央网信办督促网站和在线平台取消诱导粉丝应援打榜的产品功能，限制未成年人非理性追星活动。

The Cyberspace Administration of China urged websites and online platforms to disable functions that would induce fans to boost some stars’ popularityin a dishonest manner, and to help restrict underage fans from irrationally adoring stars.

因网络上诱导未成年人应援集资、攀比炫富、侮辱诽谤等问题突出，中央网信办决定本月起在全国范围内开展为期2个月的“清朗·‘饭圈’乱象整治”专项行动。

The Cyberspace Administration of China kicked off a two-month nationwide campaign this month to purify the online environment after it found that some netizens had lured youngsters to spend large amounts of money on stars, flaunt their wealth or become involved in mudslinging exchanges with fans of rival performers.

参考：ChinaDaily返回搜狐，查看更多