根据下面所设情景，选择恰当的选项。

1. 当你想问别人邮局在哪里时，应说：[ ]

A. What is the post office?

B. Is this a post office?

C. Do you know where the post office is?

2. 当你想问那张贺卡多少钱时，应说：[ ]

A. How much is the card?

B. How is the card?

C. How old is the card?

3. 当你想问对方是否会照相时，应说：[ ]

A. May I take your picture?

B. Can you take a picture?

C. Can you help me to take a picture?

4. 当你想问发生了什么事时，应说：[ ]

A. What happening?

B. What is happen?

C. What happened?

5. 当你想问火车站是否有许多人时，应说： [ ]

A. How many people are there in the train station?

B. Are there many people in the train station?

C. Does the train station have many people?