① by and by表示“沒多久,一會兒之后”,相當于soon或after a while。
By and by the school year will be over. 不多久這個學年就要結束了。
He'll be back by and by. 他一會兒就會回來了。
② by the by表示“順便說到”,相當于incidentally,by the way。
By the by,what happened to the boy?順便問一下,那個男孩后來怎樣了?
③ by and large表示“大體上,基本上”。
By and large,the plan is practicable. 這個方案大體上可行。
④ gradually表示“漸漸地”,相當于slowly或little by little。
The baby is gradually learning to walk. 那個嬰兒漸漸地開始學走路。