$\text{1. busiest}$
$\text{2. crowded}$
$\text{3. natural}$
$\text{4. better}$
$\text{5. beautifully}$
VII
$\text{1. prepares->prepare}$
$\text{2. most->∅}$
$\text{3. interested->interesting}$
$\text{4. will->won't}$
$\text{5. should->shouldn't}$
$\text{6. gooder->better}$
X
1. You should'nt spend a lot of time watching TV.
2. Antarctica is the coldest place.
3. Why don’t we go to Times Square to welcome the New Year?
4. A car isn't as convenient as a bicycle in towns.
5. Take the first turnin' on your right.
XI
1. Vietnamese peoples often clean and decorate their houses before Tet.
2. The air in the city is more polluted than the air in the countryside.
3. It’s very interesting to take a boat trip to the Perfume River.