It is fun to planting trees.哪错了?

It is fun to planting trees.哪错了? _______great fun it is to watch the monkeys climbing trees ! it is a fun to look at the picture when l finish it哪里错了 Trees are important _______ us.Planting trees is important _ Mr Black is planting trees and his daughter is helping______ Mr Black is planting trees and his daughter is helping_____ planting more trees is very important ___ people It is fun to do sth.句型fun的词性 It is fun?到底是It is fun to do sth 还是It is fun doing sth?It is great fun it is to . go boating what fun it is to=how____ it is fun to do 还是 doing?