MySQL多对多关系

无法创建最后一个表：（在我看来，答案应该非常简单，但不幸的是找不到它。 代码如下：

CREATE TABLE Topics ( topicId INT NOT NULL AUTO_INCREMENT, 
        topicName VARCHAR(50) NOT NULL,
        submdate DATE NOT NULL,
        accdate DATE NOT NULL, 
        comm VARCHAR(100), 
        status varchar(1) CHECK (status>0 and status<4),
        PRIMARY KEY (topicId) );


CREATE TABLE Student ( studentId INT NOT NULL AUTO_INCREMENT,
        studentname VARCHAR(50) NOT NULL,
        PRIMARY KEY (studentId) );  


CREATE TABLE TopicStudent ( topicId INT NOT NULL,
            studentId INT NOT NULL,
            PRIMARY KEY (topicId, studentId),
            CONSTRAINT Constr_TopicStudent_Student_fk
                FOREIGN KEY Student_fk (studentId) REFERENCES Student (studentId)
                ON DELETE CASCADE ON UPDATE CASCADE,
            CONSTRAINT Constr_TopicStudent_Topic_fk
                FOREIGN KEY Topic_fk (topicId) REFERENCES Topic (topicId)
                ON DELETE CASCADE ON UPDATE CASCADE
            );

创建表主题（topicId INT NOT NULL AUTO_INCREMENT，
topicName VARCHAR（50）不为空，
子日期不为空，
accdate日期不为空，
通信VARCHAR（100），
status varchar（1）检查（status>0和status
Const r\u TopicStudent
？Const和r\u TopicStudent之间是否有空格？
没有空格