Forums Scripts & Popups write scripts !

How can i write a line specified by a variable to a text file ?
with the command : /write -l5 c:\info.txt line number 5 ; This line will overwrite the 5th line in the file
But when the line is specified by the variable %line (%line = 5)
/write -l%line c:\info.txt line number %line ; this always overwrites the first line
what can i do ? please help me !

//write -l $+ %line C:\info.txt
or
//write $+(-l,%line) C:\info.txt

or
//write -l %line C:\info.txt text to write