A:Where is he?
B:Why does he want to be a teacher?
C:What does he do?
D:How old is he?
Classes start ____(in/ at)3 o'clock.
如图,图为“没有她何以为‘国’”的文字图(提示:“国”字中的“点”为台湾岛的地理轮廓图),这幅图主要告诉我们( )