Simplify the following text for a Grade 11 native English-speaking person.
Original: On 27 September , a Junkers Ju 88 returning from a raid on London was shot down in Kent , resulting in the Battle of Graveney Marsh , the last action between British and foreign military forces on British mainland soil .
Simplified: On 27 September , a Junkers Ju 88 returning from a raid on London was shot down in Kent , the last action between British and foreign military forces on British mainland soil .