in 15 minutes at half past

at half past six at half past L-----start at half past one in the afternoon. At half past three in the afternoon the chairman__the meetin We( )school at about half past four in the afternoon. The first class_______ at half past eight in or school we should arrive at school at half past seven in the morning at half past seven为什么前面用at而不用on,in,to in the morning,i get up at half past six.i brush my teeth at At twenty minutes past eight 什么意思 all the classes in the morning finsh at half past eleven.改为同 we do our homeworks at half past six in the afternoon有什么错误