foot和feet的用法区别（当foot表英尺时）请问在什么情况下用foot而又在什么情况下用feet,注：我曾在牛津英汉双解字典中级版中看到过“five foot”.所以请各位大师告诉我这foot和feet到底怎么用?

In America 1 foot = 1呎 (Originally from England but now only used in America)
1 foot, 2 feet, 3 feet, 4 feet
Feet is the plural form
1 foot = 12 inches = 1 inch = 2.54 cm
2 feet = 24 inches
1 foot 足 Most people have 2 feet

当foot表英尺时,复数为feet.但也可以不变.特别是表示人的身高时,常用单数.如：
He is six feet（foot）tall.
The building is 40 feet（foot ）high
见《英汉多功能词典）第588页等