CREATE TABLE employee (emp_fname VARCHAR, emp_num VARCHAR)
CREATE TABLE course (crs_description VARCHAR, crs_code VARCHAR)
CREATE TABLE CLASS (prof_num VARCHAR, crs_code VARCHAR)

Find the first names of all instructors who have taught some course and the course description.
SELECT T2.emp_fname, T3.crs_description FROM CLASS AS T1 JOIN employee AS T2 ON T1.prof_num = T2.emp_num JOIN course AS T3 ON T1.crs_code = T3.crs_code
SELECT "T2"."emp_fname", "T3"."crs_description" FROM "CLASS" AS "T1" JOIN "employee" AS "T2" ON "T1"."prof_num" = "T2"."emp_num" JOIN "course" AS "T3" ON "T1"."crs_code" = "T3"."crs_code"