it's no small challenge for a blog run by a group of odrinary-if ambitious-young people ,but the members of generation obama are up to the task.这句话中“不是一个小的挑战”为什么是no,而不是not; if ambitious中的if为什么要翻

it's no small challenge for a blog run by a group of odrinary-if ambitious-young people ,but the members of generation obama are up to the task.这句话中“不是一个小的挑战”为什么是no,而不是not; if ambitious中的if为什么要翻
it's no small challenge for a blog run by a group of odrinary-if ambitious-young people ,but the members of generation obama are up to the task.这句话中“不是一个小的挑战”为什么是no,而不是not; if ambitious中的if为什么要翻译成“即使”；up to the 怎么来的?

it's no small challenge for a blog run by a group of odrinary-if ambitious-young people ,but the members of generation obama are up to the task.这句话中“不是一个小的挑战”为什么是no,而不是not; if ambitious中的if为什么要翻
看到small challenge 了吗?正常的语句的话需要有个a 或者any或者some等,即a small challenge 或者some small challenges.这里用no即not a 或者说是not any.至于if ambitious翻译成即使,我不知道人家ordinary-if ambitous-young people是怎么翻译的,我的翻译是正常而又有雄心的年青人/普通而又有野心的年青人.up to the task,原意是胜任这项任务,我个人理解是:但是奥巴马这一代人却能够应付得来(应付得了开通博客这样的挑战)