Word for being asked many difficult questions

"I'm getting ready for the oral exam. I'm sure the teacher will ____ me with a lot of difficult questions."

"Grill" would be appropriate here.

Grill (verb): to subject to severe and persistent cross-examination or questioning.
[Dictionary.com]

I also thought of "give me the 3rd degree," but that generally implies that the questions are hostile or uncomfortable. "Grill" can be used for that as well, but is also appropriate for questions that are academically difficult.

You could say:

I'm getting ready for the oral exam. I'm sure the teacher will bombard me with a lot of difficult questions

Bombard someone with something: to direct so many things at someone, especially to ask them so many questions, that they find it difficult to deal with them.

Example: The children bombarded her with questions.

[Cambridge English dictionary]

Or the teacher will shoot questions at me.

To shoot questions at somebody: to ask someone a lot of questions very quickly, one after the other.

Example: He shot questions at me so quickly that I didn't even have time to answer.

[Cambridge English dictionary]

You could also say "the teacher will pepper me with questions" (mentioned by the commenters too).

Pepper (verb): to direct something suddenly and repeatedly at someone, as if attacking the person.

Example: The mayor was peppered with questions from reporters about the municipal corruption scandal.

[Cambridge English Dictionary]