例句與造句

1. By 1876, the equipment of the company included : 5 double and 6 single puddling furnaces, 9 heating furnaces, 96 nail machines, 5 trains of rolls and 5 hammers, operating on both water and steam power.
2. Together the two sites contained sixty puddling furnaces, twenty heating furnaces, fourteen trains of rolls, three rotary squeezers, nine horseshoe machines, twelve rivet machines which each produced eighty rivets a minute, ten large and fifteen small steam engines, seventy boilers, and the great water-wheel.
3. It's difficult to find train of rolls in a sentence. 用train of rolls造句挺難的