下列陈述不正确的是（ ）
A．分子可以分解成原子
B．原子由原子核和电子构成
C．阳离子得到电子变成原子
D．原子失去电子变成阴离子
A、分子和原子的联系是分子是由原子构成的，所以分子可以分解成原子，故A正确；
B、原子是由居于原子中心的带正电的原子核和核外带负电的电子构成，故B正确；
C、阳离子是失去电子的原子，再得到电子就可能又变成原子了，故C正确；
D、原子失去电子变成阳离子，故D错误．
故选D．
Traffic rules help to keep order on the road. They also help to keep people 26 . The pedestrian(行人) has as many rules to 27 as the driver of a car. You should walk on the sidewalk(人行道) or at the side of the road. Always look 28 before you walk across the street. If you like riding a bike, don’t ride in the middle of the road or run 29 red traffic lights. When you ride a bike with a friend, don’t look around or talk.If you drive a car, you should 30 at the traffic lights. You must always 31 a seat belt(安全带). Without belts 32 the driver and the passengers may be badly hurt in a sudden accident. You may not need to take a bus, but 33 if you have to travel in one. Get on or get off a bus only when it comes to a 34 . When it is full, don’t try to get inside 35 you may fall off. Traffic rules are also called Road Safety rules. The maxim(格言) for all road users is “Thinking about others”.
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