题目

如图，AD是△ABC的中线，∠ADC=45°，把△ADC沿AD对折，点C落在C′的位置，则BC′与CC′之间的关系是              . 答案：垂直且相等 I’m Chinese and I do feel _____ Chinese language is _____ most beautiful language, what’s your opinion? A. / ; the           B. the; a            C. the；/         D. / ; a