学会自我保护,对未成年人的健康成长至关重要,下列做法正确的是( )
①同学溺水,奋不顾身救援 ②公共场所,不忘观察安全出口
③面对歹徒,力求保护自己 ④网络聊天,不轻易泄露个人信息
A:①②③
B:②③④
C:①②④
D:①③④
One day,a hungry and thirsty____sees some nice grapes. He likes grapes. They are purple and ____. But the grapes are high. The fox ____get and eat them. A bird can____the grapes. She likes the sweet grapes. They are yummy. The fox is ____and angry. He says those grapes are sour. They are not____.
α、β表示平面,a、b表示直线,则a∥α的一个充分条件是( )
钱乘旦教授在《从历史学视角透视世界现代化进程》中指出:英国克服专制王权,实现权力向下转移,是其政治现代化的第一目标。英国完成这一目标是通过( )