def find_best_shifts_rec(wordlist, text, start):

    ### TODO.
    message = text
    #each start check all possible shift
    for shift in xrange (0,27):
        if start >= len(message):
            return recshift#stop when start gets to the end
        newstart = start
        message = message[:start]+apply_shift(message[start:],shift)#part of the message is shifted
        splitted_message = message[start:].split()#split into unchecked words
##        print 'shift:',shift,'  ',splitted_message
        for word in splitted_message:#check each possible word
            if is_word(wordlist,word):
                newstart = start + len(word)+1#plus the length of the valid word and a space
##                print newstart
            else:#quit the loop when the first invalid word comes
                break
        if newstart > start and start == 0:#add the first (start,shift) pair
            recshift = [(0,shift)]
        if newstart > start and start != 0:
            recshift = recshift + [(start,shift)]#add new (start,shift) pair
##            print 'after added:',recshift
            return find_best_shifts_rec(wordlist,message,newstart)