is的过去式是was，过去分词是been。is用于第三人称单数现在时。例句：That's the way it is.就是这么回事。
例句
1、The video is programmed to switch on at ten o'clock.电视机设定在10点钟自动打开。
2、The room is 15 feet in length and 10 feet in breadth.这房间长15英尺，宽10英尺。
3、Pain past is pleasure.过去的痛苦即是快乐。
4、A friend in need is a friend indeed.患难之交才是真朋友。