你必须加上 DELIMITER :
试试这个。

DELIMITER $$
CREATE TRIGGER PendingPublish 
AFTER INSERT ON TopicPending
FOR EACH ROW
BEGIN
    IF NEW.TopicApproved = 'YES' THEN
    INSERT INTO Topics (Title,Description,Question1,Qustion2,Question3,Question4,UserID)
    VALUES (NEW.Title,NEW.Description,NEW.Question1,NEW.Question2,NEW.Question3,NEW.Question4,NEW.UserID);
END IF;
END$$
DELIMITER ;