（ ）1."Is your brother in?""No,he isn't."

（ ）1."Is your brother in?""No,he isn't."
Here "in" means_____.
A.in a room B.in home C.at home D.at your family
( )2.I know that from A to Z.
Here "from A to Z"means _____in Chinere.
A.从A到Z B.距离很远 C.从头到尾 D.字母表
3.The post office has thousands of letters.A thief(小偷) is afraid of(害怕)four letters.What are they?
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