帮我翻译一下吖

From the door to enter the school the day, I understand that I grew up, even if there are too many or not, can only be in vain. Good-bye, young, good-bye, that the era of Clueless. Now, I have not had a smile that sounded a "little girl" growing up on the means that the sensible has. Inconstancy of human relationships, need cold treatment.

Good-bye, Junior

当进入学校大门的那天，我明白了我已经长大了。