by foot是一種動詞，on foot表示名詞。一般情況下，我準備步行去哪里，用by foot，一般現在時用on foot。

by foot例句

It'd take weeks to get there by foot.

徒步走到那里要好幾個星期。

Also the software provides a tool to analyze inversion results foot by foot.

STRATA還提供了分析分步反演結果的工具。

The main method of transportation in the Expo site is by foot.

世博園區(qū)內最主要的交通方式是步行。

Approaching Technology about Beat Ball by Foot in Volleyball Match

排球比賽中腳擊球技術初探。

on foot例句

he city is best explored on foot.

最好是徒步考察這個城市。

We came on foot.

我們是走來的。

I left my car in a lay-by and set off on foot.

我把車留在路側停車帶，徒步而行。

He got up at four and set out on foot to hunt black grouse.

他4點鐘起了床，徒步出發(fā)去獵殺黑琴雞。