$ cat file USA 442 India 249 UK 50$
paste - - -d, < file
USA,442 India,249 UK,50
paste - - - - -d, <input_list_before_combine.list # join every 4 lines, each "-" is one line
$ paste - - < file
USA 442 India 249 UK 50
from http://www.theunixschool.com/2012/03/join-every-2-lines-in-file.html
