A:BC=1,AC=2,AB= 3
B:BC:AC:AB=3:4:5
C:∠A+∠B=∠C
D:∠A:∠B:∠C=3:4:5
A. No, the lion is big.
B. No, it can't .
C. A duck has wings .
D. No, it lives in a forest .
E. No! A tiger has stripes .
①伤害了同学的自尊心
②是自我尊重、自我爱护
③不能做到平等待人
④从内心看不起同学
通过呼吸进入血液的PM2.5,最先到达心脏的( )