لَيْتَنِي

لَيْتَنِي is a phrase (شِبْهُ الجُمْلَةِ) consisting of an accusative particle (one of the sisters of Inna) followed by an accusative noun

PhraseParticle / NounNounParticle of protection Particle
شِبْهُ الجُمْلَةِحَرْفُ نَصْبٍ وَاسْمُ لَيْتَ اسْمُ لَيْتَ مَنْصُوْبٌ نُوْنُ الوِقَايَةِحَرْفُ نَصْبٍ مِن أَخَوَاتُ إِنَّ
PhraseCompoundan accusative noun  an accusative particle
    
Would that Iلَيْتَنِي=ي+ن+لَيْتَ
May it be that IIMay it be that
Surah/Below are the 8 verses in the holy Quran containing the phraseلَيْتَنِي
Verse
and indeed, if befalls you a bounty from Allah (SWT)وَلَئِنْ أَصَابَكُمْ فَضْلٌ مِّنَ اللهِ
certainly, they would undoubtedly say as if not there been between youلَيَقُوْلَنَّ كَأَنْ لَّمْ تَكُنْ بَيْنَكُمْ
and between him any affection “Oh! I wish I had been among themوَبَيْنَهُ مَوَدَّةٌ يَا لَيْتَنِي كُنْتُ مَعَهُمْ
4-73then I would have attained a great success”فَأَفُوْزَ فَوْزًا عَظِيْمًا
18-42
19-23
25-27
25-28
69-25
Indeed, We warn you of a near punishmentإِنَّآ أَنْذَرْنَاكُمْ عَذَابًا قَرِيْبًا
the day when man will see what his hands have sent forthيَوْمَ يَنْظُرُ المَرْءُ مَا قَدَّمَتْ يَدَاهُ
78-40and the disbeliever will say, “woe to me! would that I be dust”وَيَقُوْلُ الكَافِرُ يَا لَيْتَنِي كُنْتُ تُرَابًا
89-24He will say “Alas would that I had sent forth (good deeds) for my life (hereafter)يَقُوْلُ يَالَيْتَنِى قَدَّمْتُ لِحَيَاتِى