Explanation
Express a condition; 'if... not', 'unless', 'must'.
Formation
Verb-negative form + ないと
Detailed explanation
The ～ないと grammar point is used to express a condition, focusing on the negative consequences if the action is not performed. It can be translated as 'if... not', 'unless', or 'must' in English. The formation is simply attaching ないと to the negative form of a verb.
Examples
Asa gohan wo tabenai to, onaka ga suku.
If I don't eat breakfast, I will be hungry.
Shukudai wo shinai to, sensei ni okorareru.
If I don't do my homework, the teacher will be angry.
Juden wo shinai to, denwa ga tsukaenaku naru.
If I don't charge it, I won't be able to use the phone.
Kono jiko wo houkoku shinai to, mondai ga ookiku naru.
If I don't report this accident, the problem will become bigger.
Practice
Grammar content sourced from hanabira.org.