Complete the Words

Tree rings can help archaeologists work out when ancient wooden buildings were constructed. Because (1)tr___ add (2)o__ ring (3)ea__ year, (4)a__ because (5)ri__ width (6)dep____ on (7)cli____, trees (8)fr__ the (9)sa__ region (10)sh___ a recognizable pattern of thick and thin rings. By matching the rings in an old roof beam to a long master sequence, researchers can often identify the exact year in which the tree was cut down. This method has been used to date sites ranging from medieval churches to prehistoric villages.