N4 — outside your level filter
Modifies the end of the sentence directly and takes no だ／です, so there are no forms to conjugate.
一生に一度
isshouniichidoonce in a lifetimeN4adverb
Example sentences2
これは一生に一度のチャンスです。
kore wa isshou ni ichido no chansu desu.
This is a once-in-a-lifetime chance. neutral
一生に一度しかないんだから、思い切ってやろうよ。
isshou ni ichido shika nai n dakara, omoikitte yarou yo.
Since this only happens once in a lifetime, let's just go for it. casual