clayeyadj.粘土的clayn.黏土；泥土clay contact process粘土接触过程clay-cement mortar粘土水泥砂浆clay impervious core粘土防渗墙clay pigeon shootingph.clay working machine粘土加工机械clay-adsorbed form粘土吸附态clay particle content粘粒含量clay minerals content粘土矿物总量clay-backed cutworm泥背地老虎clay-colored stools土色粪，白陶土样大便

1. She discovered how clay beds,which existed for millions of years,were formed.
   她还发现了已经存在了数百年的粘土层是如何形成的。