[OS X TeX] help

[ludwik kowalski]

1) Thanks to all who commented on what I posted several days ago. Your  
messages convinced me not to give up, and to continue learning the  
Latex language.

2) Using TexShop I am composing an input.tex file. The file is long  
because I pasted a long text into it. Here what I would like to be  
able to do (but do not know how). Suppose I select a large number of  
lines. Is there a command for placing the % sign in front of each of  
them at once? Then I would select a small set of commands and remove  
the % from them before pressing the "typeset" button. That would be  
useful in debugging.

3) Error messages often refer to line numbers. But lines are not  
numbered. Is there a command like "go to line 123" in TexShop?

Thanks in advance.

Ludwik Kowalski, a retired physicist
5 Horizon Road, apt.2702, Fort Lee, NJ, 07024, USA
Also an amateur journalist at http://csam.montclair.edu/~kowalski/cf/