翻译一下几个英语短句

一，澳大利亚的东海岸有许多小岛屿。
The east coast of Australia has many small group of islandses

二，美国是由五十个洲组成。
The combination of the50 states form the united state of america.

三，十年前杰克就同家人分离了。
Decade years ago, Jack bower separated with family

四，在这座森林里五分之三的树已被砍掉了。

3/5 of the trees in the forest have been hewn。

五，令我们高兴的是我们队在这场比赛中胜利了。

What makes us happy is that our team won the game.