How To Use expect for auto response

sudo apt-get install expect  
expect $filename.sh  

filename.sh
#!/usr/bin/expect -f
spawn ~/work/selectdata/run.sh  
expect "please input the filename of the file which listed current directory filename"  
send -- "dat.txt\n"
expect "please input the listfilename include extension"  
send -- "dat.txt\n" 
expect "please input the resultfilename include extension" 
send -- "result.txt\n"
expect "please input the filename of the file which contain the filename of need to be selected" 
send -- "selected.txt\n" 
expect "please input the foldername which you want to create and would used as the storage for the selected file" 
send -- "selecteddata\n" 
interact