وَيَصْلَىٰ سَعِيرًا
Sentence structure
وَيَصْلَىٰ is a coordinated third-person masculine-singular imperfect with understood هُوَ as subject. سَعِيرًا is its accusative object.
Ayah summary
That person will enter the blazing Fire.
وَيَصْلَىٰ — And he will burn
Grammar: وَ coordinates; يَصْلَىٰ is a third-person masculine-singular imperfect with understood هُوَ as subject.
سَعِيرًا — (in) a Blaze
Grammar: An indefinite accusative noun functioning as the object of يَصْلَىٰ.