cant compile any cursor example - sql

Question

I'm trying to make any cursor example working, but just cant make it happen.
IDE: Oracle SQL developer
database: 10g sql oracle
I've tried this three examples, but it didn't compile well. Can someone provide me with working examples?
First one:
EDIT: works! just had 'where where'
DECLARE
CURSOR person_data_cur
as
SELECT *
FROM personal_data
WHERE where name='Karol';
BEGIN
FOR person_data
IN person_data_cur
LOOP
DBMS_OUTPUT.put_line (
person_data.surname);
END LOOP;
END;
and this:
DECLARE my_cursor1 CURSOR FOR
SELECT name, surname
FROM personal_data
WHERE name='Karol';
^error:
Error report -
ORA-06550: row 1, column 27:
PLS-00103: found symbol "FOR" when expected one of following:
:= . ( # % ; not null range default character
06550. 00000 - "line %s, column %s:\n%s"
*Cause: Usually a PL/SQL compilation error.
*Action:
or even this:
EDIT: this one is OK, just my IDE ignored first two lines, and executed others... but i guess it was OK since it wasnt inside any block or procedure
CURSOR c1
IS
SELECT course_number
FROM courses_tbl
WHERE course_name = name_in;

Answer 1

For Second Example : Your syntax is incorrect.
The pseudo code for the cursor is :
Declare
Cursor Cursor_name
is
select * from table where <Conditions>;
Begin
For cur_Rec in cursor_name
Loop
<what you want to do>
End Loop;
End;
For the third example, I believe name_in is an input parameter, please correct the syntax to :
CURSOR c1 (name_in VARCHAR2)
IS
SELECT course_number
FROM courses_tbl
WHERE course_name = name_in;
Please refer Cursor Declaration for more details