這五個詞組在含義和用法上各不相同。
一般說來，at hand的意思是“近旁”、“即將到來”（very near in time or place）; by hand的意思是“用手”、“手製的”（do something by one''s hands）；in hand的意思是“在手頭”、“正在進行中”（have something under trol or deal with something at the moment）; on hand的意思是“擁有”、“尚待處理的”（something ready for u or at the disposal of）; to hand的意思是“收到”（e to hand）。
這五個固定詞組中，hand都不用複數。
The final exam is near at hand.
期終考試即將到來。
They live clo at hand,around the er of Nathan Road.
他們就住在附近，彌敦道的拐角處。
This red carpet is made by hand.
這條紅地毯是手工做的。
This letter was delivered by hand.
那封信是派人送去的。
I have no cash in hand.
我手頭沒有現款。
I have a new work in hand.Its title is A Study of English Twins.
我正在撰寫新作《英語迷津——相似詞語辨析》。
There is,however,much work on hand.
然而，手頭還有許多工作要做。
They have a large supply of goods on hand.
他們手中有大宗貨物。
Your letter is to hand.
你的來信已收到了。
Your remittance has also e to hand.
你的彙款亦已收到。
與之類似區別的詞語有：
at heart在心底裏；在本質上by heart背誦；憑記憶i興致很高；精神蓬勃