fillin the gaps accordingto the model.
clean -- . . . . -- . . . .
. . . . -- more difficult -- most difficult
fat -- . . . . -- . . . .
. . . . -- . . . . --longest
short -- . . . . -- . . . .
interesting -- . . . . -- . . . .
beautiful -- . . . . -- . . . .

большое спасибо

clean-cleaner-cleanest,difficult -..-..,fat-fatter-fattest,long-longer-longest,short-shorter-shortest,interesting-more interesting-most interesting,beautiful-more beautiful-most beautiful