this piece of cloth is three times as long as that one

这块布料的长度是那一块的三倍。
值得注意的是这句话和下面一句的区别：
This piece of cloth is three times longer than that one.
翻译是：这块布料的长度比那一块长三倍。
亦即：这块布料的长度是那一块的四倍。

这块布是那块的三倍长。

这句话和下面一句有区别：
This piece of cloth is three times longer than that one.
这块布料的长度比那一块长三倍（这块布料的长度是那一块的四倍。）

这块布是那块的三倍长。

哦哦，ls正解~