List the dates of enrollment and completion of the student with personal name "Karson".
SELECT T1.date_of_enrolment ,  T1.date_of_completion FROM Student_Course_Enrolment AS T1 JOIN Students AS T2 ON T1.student_id  =  T2.student_id WHERE T2.personal_name  =  "Karson"
dates of enrollment and completion refers to date_of_enrolment and date_of_completion; student with personal name \"Karson\" refers to WHERE T2.personal_name = \"Karson\"; joining tables to match student ID and personal name involves JOIN ON condition with student_id.