Sample Infinitive: "to <verb>", such as "to eat".
His work sheet had the following sample sentences:
1. This is a place for us to play baseball.
2. This is a place to take a bath.
3. This is a machine to keep you warm.
4. This is a machine to take pictures.
5. This is a machine to play music.
6. This is a machine to clean the room.
7. This is a machine to sell tickets.
While I have no issues with numbers 1 and 2, my confusion lies in numbers 3 to 7. I thought about replacing "to" with "that" (and modify the verb as needed), but that brings me out of the topic of infinitives. I also tried "This machine is" instead of the current sentence, but that speech style sounds rather archaic.
In particular, I have trouble with "This is" in the sentence, because a phrase like "A machine to take pictures" sounds okay.
Any thoughts about this? Or maybe I'm thinking too much about something silly? Any help would be appreciated!
These sentences are all good, with the minor exception of Number 6, which would more normally read "This is a machine to clean rooms."
The infinitive often tells us the purpose, the use, the reason for something.
I don't know what your native language is; many European languages use the infinitive in much the same way.
success to you