"To have a lot on your plate" Eg; “Forgive me, but I’ve had a lot on my plate.” or “Sorry, I can’t do that right now… I have enough on my plate as it is.” "To bite off more than you can chew” Eg; “We planned to see too many landmarks in this city in one day. I think we bit off more than we could chew.” or "I signed up for five advanced courses this term, but between the exams and the extra assignments, I definitely bit off more than I can chew." Have you ever used these expressions before?