关于by的短语意思by hand 和 little by little

一、by hand
(1) 用手工(即不是用机器或其它手段).如：
The letter was written by hand.这封信是用手写的(即不是打印的).
My shoes were made by hand.我的鞋是手工做的(即不是机器做的).
(2) 用专人(即不是通常邮寄等).如：
Did the letter come by hand or through the post?这封信是专人送来的还是邮寄来的?
二、little by little,逐渐地
例句与用法:
His English is improving little by little.
他的英语渐有提高.
Little by little the snow disappeared.
雪渐渐消失.
He has changed year by year and little by little.
他随时间逐渐改变.
Little by little; gradually.
一点一点地；逐渐地