Unit2 This is my sister.提高练习题用am,is,are填空来源:学科网Z1Excuse me! _ this your eraser? 2What _ those? _ they birds? 3This _ his ruler. Where _ my ruler? 4I _ in Class Three. _ you in Class Three,too? 5_ these her English books? 6Those _ their apples. Where _ his apples? 7She _ eleven. How old _ that boy? 8He _ my friend. _ your friend a boy or a girl? 9_ those maps? N