They don’t know where they should put the mat.

• They don’t know where to put the mat.

The rules didn’t specify who I should speak to in case of an emergency.

• The rules didn’t specify who to speak to in case of an emergency.

Hayley wondered how she could ride the scooter.

• Hayley wondered how to ride the scooter.

Let us decide when we should start the project.

• Let us decide when to start the project.

Could you tell me where I can find a good hotel?

• Could you tell me where to find a good hotel?

We must find out what we are to do next.

• We must find out what to do next.

A good dictionary tells you how you should pronounce the words.

• A good dictionary tells you how to pronounce the words.

They are not sure who they will meet at the entrance.

• They are not sure who to meet at the entrance.

She can’t remember when she has to turn off the oven.

• She can’t remember when to turn off the oven.