by accident偶然, 不小心
by chance偶然, 意外地
by mistake錯(cuò)誤地，無意中（做錯(cuò)）
by far到目前為止
by hand 用手
by heart熟記
by all means盡一切辦法, 一定
by no means決不
by means of用...方法，依靠
by oneself單獨(dú)，獨(dú)自地