Task: Text to Code
Input (English): Step 1: For each row in Student table, find the corresponding rows in Enrolled_in table.
Step 2: find the average Grade in the results of step 1 whose LName equals Smith
Output (English): SELECT Avg ( T2.Grade ) FROM Student AS T1 JOIN Enrolled_in AS T2 ON T1.StuID = T2.StuID WHERE T1.LName = "Smith"