Oh! Thank you Dr.Ernest. Both Cheng Wei Lee and I are asians and we are not familiar to the English naming that much...
In the past, I think that
Tim is shortform of Timothy
Jim is shortform of Jimmy
The shortform of a name is fetched from starting words...
Cool... I got a new native English knowledge today...

Co-author of SCMAD Exam Guide, Author of JMADPlus
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