现有火柴、一张干燥的白纸、一个光洁干燥的玻璃杯、澄清的石灰水，请你设计一个小实验证明纸张燃烧产物是二氧化碳和水．（简要写出实验步骤、现象和结论）
Also when you write your goals in a particular way you are able to make yourself continuously ______ situations that will bring you nearer to your goal.
A．aware of
B．worried about
C．familiar with
D．accustomed to
下列气体不会造成空气污染的是[ ]
A．N2
B．NO
C．NO2
D．SO2
