A:只有Na2O
B:只有Na2O2
C:Na2O和Na2O2
D:无法确定
—No, Kangkang is ____(缺席) because he is ill.
找出画线部分发音不同的选项。
①____ A.bags B.cats C.dogs
②____ A.buses B.boxes C.cups
③____ A.usually B.casual C.speak
④____ A.books B.hands C.caps
⑤____ A.oranges B.lakes C.cakes