步: Ⅰ名词1.(步度; 脚步) pace; step 短语和例子正步 parade step; goose step; 寸步难移 in difficult pass; can not move a single step; 大步前进 advance with big strides; 快步走 walk at a quick pace; 学步 learn to walk; 散步
步步: step by step; at every step 短语和例子步步紧跟 follow at every step; 步步留心 be careful of every step; 步步小心 pick one's steps
换: 动词1.(给人东西同时从他那里取得别的东西) exchange; barter; trade 短语和例子用大米换布 exchange [barter] rice for cloth; 用鲜血换来的教训 a lesson paid for in blood; 那男孩用他的刀子换了一个板球棒。 the boy traded his knife for a cricket bat