I.
1 primary
2 uniform
3 north
4 large
5 decided
6 century
II.
1 if students go to the USA, they will visit the National Museum.
2 if the weather is warm, we will go to the zoo.
3 if it rains, I will stay at home.
4 if the weather is fine, she will go to the park.
5 If we don't go to the zoo, we will go to the circus.
III.
1 another
2 other
3 other
4 another
5 another
IV.
1 interested in
2 take the exams
3 brave
4 go camping
5 take part in
6 mountaineering