A:浮力不变,船身下沉些
B:浮力不变,船身上浮些
C:浮力减小,船身下沉些
D:浮力增大,船身上浮些
Tom and his sister ______ to the barbecue last Saturday.They were very happy.
五代十国中,五代相继统治的地区是 ( )
读《鱼,我所欲也》,“非独贤者有是心也,人皆有之,贤者能勿丧耳。”中的“是心”是指____