unless
/ənˈles/conjunction
- except if (used to introduce the case in which a statement being made is not true or valid)除非; 若不:
unless you have a photographic memory, repetition is vital
除非你有过目不忘的记忆力, 否则重复是非常必要的
manuscripts cannot be returned unless accompanied by a self-addressed envelope.
除非附有写明自己地址的信封, 否则原稿是不能退的。
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