题目

____ is known to all ___ Taiwan is ___ of China. A. As, that, a part        B. As, which a part C. It, which, a part D. It, that, a part 答案：D如图，已知P为锐角△ABC内一点，过P分别作BC，AC，AB的垂线，垂足分别为D，E，F，BM为∠ABC的平分线，MP的延长线交AB于点N．如果PD=PE+PF，求证：CN是∠ACB的平分线．