FTP script to transfer textfiles

hi..

i would like to ask if it possible for a ftp script to transfer only text files in
the directory and sub directories instead of the whole folder over. The filename of
the text files are unknown before transfering.

if possible can anyone provide some sample.

and also

the ftp script below enables me to transfer the folder over to the remote server
however it keep running in a loop. how can this problem be solved

#!/bin/sh
USER=root
PASSWD=daybreak

cd /home/student/Desktop
# this will get everything under /usr2/u/ls-2000/QjobSpec and place
# it into a folder called rvsi2 which is only created when this
# script is executed
wget -r ftp://${USER}:${PASSWD}@rvsi2/\/usr2/u/ls-2000/QjobSpec
# the data you download will be sit under
# /home/student/this/ysw2f011//home/student/mp3/chinese
# you can move it up by:

cd /home/student/Desktop//QjobSpec
mv QjobSpec /home/student/Desktop
cd /home/student/Desktop

# Remove the files on the remote host.
ftp -n -i rvsi2 <<EOF
user root daybreak
cd /usr2/u/ls-2000/QjobSpec
binary
quit
EOF
exit


thanks