（1）     GWD-17-Q18A

Over the course of the eighteenth century, the average output of ironwork tripled as a result of several improvements in blowing machinery and because coal replaced charcoal as the fuel used in the smelting of iron ore.

1. Over the course of the eighteenth century, the average output of ironwork tripled as a result of several improvements in blowing machinery and because coal replaced charcoal as the fuel used in the smelting of iron ore.

2. Over the course of the eighteenth century a tripling in the average output of ironwork was due to the replacement of charcoal by coal for the fuel used in the smelting of iron ore, in addition to several improvements in blowing machinery.

3. With charcoal’s being replaced by coal as the fuel used in the smelting of iron ore and several improvements in blowing machinery, the average output of ironwork tripled over the eighteenth century.

4. The replacement of charcoal with coal for the fuel used in the smelting of iron ore and several improvements in blowing machinery, the average output of ironwork tripled over the eighteenth century.

5. Charcoal being replaced by coal as the fuel used in the smelting of iron ore, and several improvements in blowing machinery, which tripled the average output of ironwork over the course of the eighteenth century

问一下倍数词的用法，像DOUBLE这种词不是只有主动么？还是可以被动表示主动？没有DOUBLING这种用法把