What is the crucial structural distinction between “jāʾa al-ṭiflu yabkī” and “jāʾa al-ṭiflu wa-huwa yabkī”?

Supplementary Practice 5: Textual Analysis, Scope of Meaning and Rhetorical Judgment

• Both put wāw immediately before a bare imperfect
• The first imperfect becomes a past verb
• The second uses a nominal clause beginning with huwa
• The second is necessarily parenthetical