what's the best environment to exercise Perl?

[John Bokma]

I'm sorry, My date and time is real.

Top posting means that you reply in the wrong place. Fix it.

 

[John Bokma]

could you help me how to set cursor automatically stay below quoting?

It should start on top. Why? Because you can do the second good thing in
replying, namely removing lines (snipping) you *don't* reply to.

I use Agent, this software's default setting is that cursor
automatically stay on the top of quoting.

Good thinking.

I asked a man who knows the history of Usenet, He said that reply in
top or bottom is not a rule people must obey, that just a custom of
NNTP client,

So much for his history knowledge.