SQL & PL/SQL

Hey guys, I am trying to create a simple trigger to implement an cascaded updated ...

CREATE OR REPLACE TRIGGER UCRI_CA_G
BEFORE UPDATE OF CA_CODE ON CONSERVATION_AGENCY
FOR EACH ROW

--BEGIN
UPDATE GRANTS SET CA_CODE = :NEW.CA_CODE WHERE CA_CODE = :OLD.CA_CODE;
--END;

I don't understand what the incorrect syntax is here, could someone please give me a hand?