verb+ing forms

English as a Second Language English Vocabulary, Grammar and Idioms
1

I don’t know what the school is thinking[color=red] having a wrestling unit.

—From Diary of a Wimpy Kid

What information does the red part give us?

Thanks.

2

In “I don’t know what the school is thinking”, the speaker is questioning or expressing surprise at the school’s behaviour. “having a wrestling unit” explains what the school is doing that has prompted this reaction.

I assume a “wrestling unit” is a course/department that teaches wrestling.

3

Can we say “I don’t know what the school is thinking [color=red]to have a wrestling unit”? If so, what’s the difference?

4

I guess some people might say “…to have a wrestling unit”, and there no difference in meaning, but to me it seems iffy. If you want to use a preposition, I prefer “I don’t know what the school is thinking by having a wrestling unit”. Opinions on this may differ between speakers.