Complex sentence: Six years later in 1968 the third child was born, Vahid Mustafayev.In the year 1990 he married the 21 years old Ingeneer Student Rafiga Mustafayeva (Bagirova).
Split into simpler sentences: Six years later in 1968 the third child was born, Vahid Mustafayev. In 1990 he married a 21 years old engineer student Rafiga Mustafayeva (Bagirova).