1、It is so good that it should increase the grade.
2、~~~was~~~~~~~~~~~~~~~~~~~~~~~increased~~~~~~~~~.
3、~~~has~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~d~~~~~~~~~~~~~~~~~~~
4、~~~has been~~~~~~~~~~~~~~~~~~~~~~~~~~d~~~~~~~~~~~~~
5、`~~had~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~d~~~~~~~~~
6、~~~has beeing~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
7、~~~should have~~~~~~~~~~~~~~~~~~~~~~~d~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
8、~~~must have been~~~~~~~~~~~~~~~~~~~~d~~~~~~~~~~~~~~~~~~~~~~~~~~~
一般现在时:He is a first—year student.