A:①和②
B:①和④
C:③和④
D:②和④
Come on! The train is leaving, or we'll miss it.
78.6-(56.3-42.6)×2.8=____
看一看,读一读,选一选。
A. Wow! B. How beautiful! C. She's my mother. D. Really? E. Who's that boy?