复数： filters
第三人称单数： filters
过去式： filtered
过去分词： filtered
现在分词： filtering

You should at least boil it or use a filter .

你至少需要把水煮沸或者是过滤一下。

The left column shows the available filter types .

左边一列显示了可用的过滤器类型。

How often should I change my air filter ?

多久该换一次空滤呢？

But does this apparent support filter into the public consciousness ?

不过这种表面的支持，能否渗透到公众的意识当中呢？

The image below is a single 20-second exposure taken with a red-green-blue filter .

下图是用红-绿-蓝滤光片拍摄的单一20秒曝光照片。