A:①②
B:①④
C:②③
D:①③
示例:当窗吹喇叭——名声在外
①老鼠过街——____
②泥菩萨过河——____
③小葱拌豆腐——____
Hello, ____ ____ Lin Tao speaking. ____ ____ Tom?
—Excuse me! You can't take photos here.Look at the sign. It says “NO PHOTOS”.
— Sorry,I _________ see it and I _______ do it.
如图,在△ABC中,AB=AC,DE是过点A的直线,BD⊥DE于D,CE⊥DE于点E;
(1)若B、C在DE的同侧(如图所示)且AD=CE.求证:AB⊥AC;
(2)若B、C在DE的两侧(如图所示),其他条件不变,AB与AC仍垂直吗?若是请给出证明;若不是,请说明理由.