Cain made love to his wife, and she became pregnant and gave birth to Enoch. Cain was then building a city, and he named it after his son Enoch.
NIV
And Cain's wife [one of Adam's offspring] became pregnant and bore Enoch; and Cain built a city and named it after his son Enoch.
AMP
And Cain knew his wife; and she conceived, and bare Enoch: and he builded a city, and called the name of the city, after the name of his son, Enoch.
KJV