Today the canal is still being used.Ships can be seen moving on ____
问题描述：
Today the canal is still being used.Ships can be seen moving on ____
Today the canal is still being used.Ships can be seen moving on ____ water now and then.But it is no longer ____ busy water highway.
A.a; the B.the;不填 C.不填; a D.the; a
答
D moving on the water 在水上^^不可数
a busy water highway 繁忙的水上'高速公路'
highway可数