1.一个人不努力就能获得成功似乎是不可能的.2.这位科学家感到很沮丧,因为他的理论得不到他人的认

It's almost impossible to achieve success without working hard.“一个人”不要翻译,在这句里是冗余的.
The scientist is frustrated because his work has not been acknowledged.理论 和 认可 直译 是 theory ,recognized 比较习惯的表达方式是 work ,acknowledged .
Most researchers consider green house gases to be the main culprit in the rapidly melting polar ice cap. 我认为把元凶译为 the main culprit （主要元凶）比较好.rapidly 是我为句子润色而加的.
The part of the movie that interested me the most was the beauty of the Alps.
Not until the goundwater had turned red did the local government realize the severity of the pollution in the area.
我是加拿大人,英语是我第一语言

1 A person can not work hard to get success seems impossible.
2 The scientist was very frustrated because he was not recognized theories of others.
3 Most researchers around the world believe ...