唾液淀粉酶的激活剂是
A. 钠离子
B. 氯离子
C. 铜离子
D. 硫酸根离子
In rising intonation, the voice ______ at the end.
A. falls
B. goes up
Do you like it?
A. This sentence has rising intonation.
B. This sentence has falling intonation.
It's going to snow today.
A. This sentence has rising intonation.
B. This sentence has falling intonation.