sent = input('give me a sentence, please: ','s')
spaces = sent==' ';
s1 = sent;
words = sum(spaces) + 1
starts = [1 (find(spaces) + 1)]
diff = 'a'-'A'
sent(starts) = sent(starts) - diff;
char(sent)
nospaces = ~spaces
sent(nospaces) = s1(nospaces) - diff;
char(sent)