1. Q: What is this?

A: It’s a lock. / It’s a padlock.

2. Q: What is it used for?

A: It’s used for locking things up.

or

A: It’s used for keeping things safe and secure.

3. Q: Is it locked or unlocked?

A: It’s unlocked. (Look at the picture.)

4. Q: How do you unlock it?

A: You use a key to unlock it.

or

A: You unlock it by using a key.

5. Q: What can you do if you lose the key?

A: You can find a spare key.

or

A: You might have to break open the lock.

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