Explanation
Expresses 'not impossible' or 'might as well'.
Formation
Verb-ないform + なくもない, い-Adjective－い + くもない, な-Adjective + でもない, Noun + でもない
Detailed explanation
The ～なくもない grammar point is used to suggest that something is not necessarily preferred or likely, but it's also not out of the question. It can often translate to 'It’s not a bad idea' or 'It might be feasible.'
Examples
Kare ga mou sugu modoru nara, matsu naku mo nai.
If he’s coming back soon, waiting wouldn’t be a bad idea.
Kono hon ga yaku ni tatsu nara, kau naku mo nai.
If this book is useful, it might not be a bad idea to buy it.
Tenki ga yokereba, pikunikku ni iku naku mo nai.
If the weather is nice, it wouldn't be impossible for us to go on a picnic.
Sono purojekuto ga seikou sureba, puromooshon mo arienaku mo nai.
If that project succeeds, a promotion might not be out of the question.
Practice
Grammar content sourced from hanabira.org.