A：①②③
B：①②④
C：①④
D：①③
—Sorry, Miss Liu. I forgot __________ my homework to school.
— __________ so careless, Sandy.
Boop…Boop…Can you hear a train? No. I hear .
28＋____=30
87＋____=90
59＋____=60
46＋____=50
35＋____=40
72＋____=80
