I. 1. competition. 2. lose. 3. luck. 4. tried. 5. believe. 6. communication. 7. mind. 8. give up. 9. tour. 10. a chance.
II. 1. historical. 2. successful. 3. Africa. 4. funny. 5. scientific.
III. 1. will not go. 2. plays. 3. doesn't. 4. saw. 5. have cleaned. 6. have been walked. 7. is doing.
IV. 1. c). 2. a). 3. c). 4. b). 5. c).
Long - longer -the longest
short - shorter - the shortest
clever - cleverer - the cleverest
tasty - tastier - the tastiest
funny - funnier - the funniest
big - bigger - the biggest
thin - thinner - the thinnest
young - younger - the youngest
red - redder - the reddest
white - whiter - the whitest
black - blacker - the blackest
new - newer - the newest
fat - fatter - the fattest
slim - slimmer - the slimmest
nice - nicer - the nicest