Tell me the personal name, family name, and author ID of the course author that teaches English.
select t1.personal_name, t1.family_name, t2.author_id from course_authors_and_tutors as t1 join courses as t2 on t1.author_id = t2.author_id where t2.course_name = "English"
How about that of course French.
select t1.personal_name, t1.family_name, t2.author_id from course_authors_and_tutors as t1 join courses as t2 on t1.author_id = t2.author_id where t2.course_name = "French"
Tell me the personal name, family name, and author ID of the course author that teaches the most courses.
select t1.personal_name, t1.family_name, t2.author_id from course_authors_and_tutors as t1 join courses as t2 on t1.author_id = t2.author_id group by t2.author_id order by count(*) desc limit 1