A:蛲虫
B:钩虫
C:蛔虫
D:血吸虫
①画△ABC的中线CD;
②画△ABC的角平分线AE;
③画△ABC的高BF;
④画出把△ABC沿射线BF方向平移3cm后得到的△A1B1C1.
A.—Is this your skirt,cat?
—Oh,yes.Thank you.
B.—I like this book.
—Me too.
C.—This is my new T-shirt.
—How nice!
被认为是欧洲开始从中世纪向近代社会过渡的标志是( )