Sentence:  In Great Britain <WSD>ledgers</WSD> that were placed outside of churches are sometimes termed external <WSD>ledgers</WSD>, while those placed within churches are called internal <WSD>ledgers</WSD> ... <WSD>Ledgers</WSD> generally sit directly on the ground or on low supports. 
Meaning of the word marked with <WSD> tags:  A large, flat stone, especially one laid over a tomb.