زَيْدٌ يَكْتُبُ وَيَشْعُرُ
Zayd writes and composes poetry.
Zaydun is the subject. “Yaktubu” is a verbal predicate, with an understood subject referring to Zayd; the whole verbal clause occupies a nominative predicate position. “Wa-yashʿuru” is a second coordinated verbal predicate, likewise attributed to Zayd.
The connector makes both attributes share one predicative setting. Without it, a second independent utterance might be understood, but the deliberate coordination of the two predicate clauses would no longer be expressed in the same way.