3.5米的英语怎么说

3.5米的英语是 "three point five meters"。
"Meter" 这个单词来源于希腊语 "metron"，意为 "a measure"。在英语中，"meter" 是一种长度单位，符号为 "m"。
例句：
The room is three point five meters long.
(房间长3.5米。)
The height of the building is about three and a half meters.
(这栋建筑物的高度大约是3.5米。)
The pool is three point five meters deep.
(这个游泳池深3.5米。)