sentences:  The western part of the south arcade was added in about 1330–40 when the nave seems to have been extended westwards to its present length of six bays.At the same time the clerestory was added to the nave and the chancel was rebuilt with its present Decorated Gothic east window.The north aisle may also be 14th century, but rebuildings and alterations in 1649 and 1879 have obscured the evidence for its original appearance.