Here’s a sketchy, general structural analysis of Genesis 4.

A. Adam knows Eve, vv 1-2 (Cain born/Abel born//Abel flocks/Cain ground)

B. Cain and Abel, vv 3-16

C. Cain knows wife, v 17-18

B’. Lamech, vv 19-24

A’. Adam knows Eve, vv 25-26

B breaks down as follows:

A. Offerings to Yahweh, vv 3-5 (Cain/Abel//Abel/Cain)

B. Yahweh appears to Cain, vv 6-7 (Yahweh monologue)

C. Cain kills Abel, v 8

B’. Yahweh confronts Cain again, vv 9-15a (Yahweh/Cain/Yahweh/Cain/Yahweh)

A’. Yahweh appoints sign; Cain leaves presence of Yahweh, v 15b-16

Significantly, the story of Cain and Abel uses the name Yahweh eight times.