I think that it might be hard

[GoldfishLord]

1. I think that it might be hard.
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Q: I'd like to know what the red part should be changed to, when we change sentence 1 into past tense.

 

[Tdol]

You can drop that, though.

 

[emsr2d2]

And a sentence starting "I'd like to know" isn't a question so preceding it with "Q:" doesn't work. To make it a question, it would need to start "What should the red part be changed to ...?"