He's realistic enough to know he's not going to succeed overnight.

他很现实，知道自己的成功不会一蹴而就。

youdao

But you can succeed if you don't expect overnight success.

不过，如果你不是希望一夜暴瘦的话，还是有可能成功的。

youdao

Major General WILLIAM CALDWELL (U.S. Military Spokesman): Although there is reason to be optimistic that this plan will succeed, it is important to acknowledge that it will not turn the security situation overnight.

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