καὶ ἐὰν ἀσπάσησθε τοὺς φίλους ὑμῶν μόνον, τί περισσὸν ποιεῖτε; οὐχὶ καὶ οἱ τελῶναι οὕτω ποιοῦσιν;

1. καὶ
   and
2. ἐὰν
   if
3. ἀσπάσησθε
   you greet
   greet
4. τοὺς
   the
5. φίλους
   friends
6. ὑμῶν
   your
7. μόνον
   only
8.  
   ,
    
9. τί
   what
   something
10. περισσὸν
    excessive
    excess, extraordinary
11. ποιεῖτε
    do
    you do
12.  
    ;
     
13. οὐχὶ
    not
14. καὶ
    and
15. οἱ
    the
16. τελῶναι
    tax collectors
17. οὕτω
    thus
18. ποιοῦσιν
    they do
    they make, do
19.  
    ;
     

And if you greet only your friends, what extraordinary thing are you doing? Do not even the tax collectors do the same?