1. Q: What can you buy at this machine?

A: You can buy tickets.

or

A: You can buy tickets for the train.

2. Q: What can you use to pay for the tickets?

A: You can use cash or a credit card.

3. Q: Which button do you push if you want to cancel a transaction?

A: You push the red "cancel" button.

4. Q: What kind of bills does this machine accept?

A: It accepts ones, five, tens, or twenties.

or

A: It takes ones, five, tens, or twenties.

5. Which button do you push to listen to instructions?

A: You push the audio button.

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