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【单选题】
用实际参加化学反应的离子符号来表示化学反应的式子叫离子方程式，在离子方程式中，反应前后的电荷是守恒的，原子个数也是守恒的．现有如下离子方程式：RO 3 n- +F 2 +2OH - =RO 4 - +2F - +H 2 O，由此可知在RO 3 n- 中，元素R的化合价是（ ）A.
+4
B.
+5
C.
+6
D.
+7
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【简答题】阅读理解 This afternoon Daddy and I went out for a walk. On the way we saw a lot of people. We went up and hada look. Oh dear! What did we-see? There was a donkey in the middle of the road.lt would not mo...
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【单选题】Sor ry， I didn’t hear you. I to the music.
A.
just listened
B.
was just listening
C.
has just listened
D.
had just listened
【单选题】Didn’t you see the man () ?
A.
I nodded just now
B.
whom I nodded just now
C.
I nodded to him just now
D.
I nodded to just now
【简答题】I didn’t cry when I learned I was the parent of a disabled child. I just sat still and didn’t say anything. When Jenny was old enough, I sent her to a kindergarten. On the first morning, Jenny spent h...
【单选题】Yesterday evening. I went out for a walk with my mother. On the way. we met a foreigner (外国人). He asked me the way to the Hot Spring Hotel. I told him to walk along the mad and take the third turning ...
A.
True.
B.
False.
【单选题】If I ______ in this cap, I wouldn't feel so conspicuous.
A.
wasn't dressed
B.
didn't dress
C.
weren't dressed
D.
don't dress
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