如果（它）不存在，如果没有……，如果（某人）没有……
1. if (it) doesn't exist, if there is no ..., if (one) doesn't have ...
expressions (phrases, clauses, etc.)
colloquial
word usually written using kana alone
如果不……，除非……
2. if not ..., unless ...
auxiliary
expressions (phrases, clauses, etc.)
colloquial
word usually written using kana alone
必须……
3. have to ..., must ...
expressions (phrases, clauses, etc.)
auxiliary
colloquial
abbreviation
word usually written using kana alone
