Sqlsever comment and Multiline comment _mssql

Environment: SQL Server 2008 R2
Question: The annotation usage in SQL Server is not clear.

Solve:

Single-line Comment:--
Multi-line Comment:/*......*/

Use examples:

Single-line Comment:

-The column ' Student.sname ' in the select list is not valid because the column is not included in an aggregate function or a GROUP by clause. 
SELECT Student.sno,sname,avg (grade) as Avg_g 
From STUDENT,SC  www.jb51.net 
WHERE student.sno=sc.sno and cno<> ' 008 ' 
GROUP by Student.sno-not added Student. The column name ' Sno ' is ambiguous. Having 
MIN (grade) >= 60 

Multi-line Comment:

 
/* Grant all permissions to the Student table and Course table to the user U2 and U3  
 Grant all priviliges www.jb51.net on   
        table Student, Course  
           to U2, U3;  
Grant the query permissions on the table SC to all users  
grant SELECT on table SC to public  
; 
Grant the user U4 GRANT UPDATE (Sno) the Query Student table and the permission to modify the student number  
, SELECT on  
           table Student to U4;  
 REVOKE UPDATE (Sno) on the TABLE Student from U4 the user U4 modify the student number's permission; 

Effect Chart: