A:木炭在氧气中燃烧,生成灰色固体
B:硫在空气中燃烧,发出淡蓝色火焰,放出有刺激性气味的气体
C:红磷在空气中燃烧产生大量白雾
D:铁丝在氧气中燃烧,火星四射,生成四氧化三铁
产生挫折的原因有哪些?
下面是晓丽从生活中收集到的一些光现象实例,以下说法正确的是( )
Many popular children's books ____ ____ by Doctor Seuss in the 20th century.
My father told me ________ football in the street. It's dangerous.