【C12】A．producedB．createdC．improvedD．facilitated

A．thoughtB．createdC．supposedD．caused

【C6】A．employedB．createdC．operatedD．controlled

A．stoppedB．createdC．calledD．mentioned

【C16】A．moreB．enlargedC．improvedD．increased

【C19】A．producedB．createdC．manufacturedD．invented

【C12】A．designedB．createdC．inventedD．bought