摘道钉时，必须手心向下栽道钉，用锤轻轻稳牢。随后再用力钉下去，防止砸手伤人。
参考答案：对
With so many people __in English every day, we can see it will be more and more important ___ a good knowledge of English．
A．to communicate, have
B．communicate; having
C．communicating; to have
D．communicated; to have
煤粉细度是如何调节的？
