A:驽钝 契机 留滞 蓬蒿
B:涟漪 荇藻 聒噪 敦厚
C:通霄达旦 提心掉胆 折中是非
D:癖性 襁褓 恻隐 明信片
— What do you want to be in the future, Nick?
— I want to be _____ pilot(飞行员), it is _____ exciting(令人激动的,兴奋的) job.
(Ⅰ)求证:PC⊥BC.
(Ⅱ)求二面角M﹣AC﹣B的大小.
____ ____ ____,Dale's brother or his sister?
如图,某同学将一块三角形玻璃打碎成三块,现要到玻璃店去配一块完全一样的玻璃,那么最省事的办法是( )