Old – older/elder – oldest/eldest
Safe – safer – safest
Young – younger – youngest
Well – better - best
Useful – more useful – most useful
Pretty – prettier - prettiest
Good – better - best
Friendly – friendlier – friendliest
Hot – hotter - hottest
Busy – busier - busiest
Healthy – healthier - healthiest
Lovely – lovelier - loveliest
Beautiful – more beautiful – most beautiful
Fat – fatter - fattest
Interesting – more interesting – most interesting
Convenient – more convenient – most convenient