Trying to run an update SQL statement to update students roommate information for the current semester and next semester and it throws a "ORA-00933: SQL command not properly ended" at me...

Here is the statement that is failing:

DECLARE
current_semester varchar (4);

BEGIN

current_semester := '2131';

update hawaii.a
set user_def_text06 = ' ';

UPDATE hawaii.a set user_def_text06 =
(select my_bed FROM hawaii.b
WHERE hawaii.b.unique_id = hawaii.a.special_id
AND hawaii.b.termid = current semester)
WHERE EXISTS
(select my_bed FROM hawaii.b
WHERE hawaii.b.unique_id = hawaii.a.special id
AND hawaii.b.termid = current_semester)

commit;
end;
.
run;


Can someone help me identify why is oracle giving the error:

Thanks.