Derrick and I have been laying out the system of irrigating ditches.德里克跟我在一起修建那个灌溉网.The rain has filled up the ditches again.雨水又把沟渠给灌满了.The fields are crisscrossed by irrigation canals and ditches.田野上沟渠纵横.Deep ditches, d...
这船的龙骨是钢制的.The keel of the boat was made of steel.木制的椅比钢制的椅要舒服些.A wooden chair is more comfortable than a metal one.这类工具是钢制的.Tools of this kind are made from steel....