Below is an context that describes a sql query, paired with an question that provides further information. Write an answer that appropriately completes the request.  # noqa: E501
### Context:
CREATE TABLE Student_Enrolment (semester_name VARCHAR, semester_id VARCHAR); CREATE TABLE Semesters (semester_name VARCHAR, semester_id VARCHAR)
### Question:
Which semesters do not have any student enrolled? List the semester name.
### Answer:
SELECT semester_name FROM Semesters WHERE NOT semester_id IN (SELECT semester_id FROM Student_Enrolment)