X. 1,My sister is not old enough  to drive a car

2,The radio is big enough to put it in your pocket

3,This coat is cold enough to wear it in winter

4,She is beautiful and intelligent enough to become Miss World 

5,The weather was fine enough to go camping 

6,Those apples are not ripe enough to eat them

7,Mr.Robinson is poor enough to buy a house 

8,The worker is clever enough to make fine things from wood

III,  1.She works hard 

2.He thinks quickly

3.They learn well

4.Lan smiles happily

5.Nam plays soccer skillfully

6.Ba drives carefully 

7.We run fast

8.They come lately

IV,  1.slowly

3. excellently

2.good

4.bad

5.quickly

6.careful

7.soft

8.happily

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