Answer: C) Starting a messy and complicated problem.
Explanation for this question is being written.
Answer: C) Important enough to make the effort.
Answer: D) Piece of cake.
Answer: D) Idiom
Answer: D) The homework was very easy.
Answer: B) Strongly
Answer: B) Took on too much.
Answer: C) A senseless or hopeless attempt to do something.
Answer: D) Through labour.
Answer: C) Piece of cake.
Answer: B) This means that these researchers have long led efforts in the field.
Answer: B) I've looked everywhere for it.
Answer: A) Study
Answer: A) Hard nut to crack.
Answer: A) Dustin is always ready to go fishing without hesitation.
Answer: A) Go study.
Answer: A) Hit the books.
Answer: D) A wild goose chase.
Answer: C) To start all over again.
Answer: B) To push through something difficult with determination.
Answer: A) Run out of steam.
Answer: C) It's so easy.
Answer: C) You should put in additional effort to achieve a better result.
Answer: A) Jumping through hoops.
Answer: A) It is a small part of something much bigger.
Answer: C) Work hard.
Answer: C) Time
Answer: C) Was discouraged from trying.
Answer: D) Midnight
Answer: B) Be tied up with.
Answer: B) To study hard for a long time.
Answer: C) Face a difficult issue with courage.
Answer: C) Try to gain two things at once and fail with regards to both of them.
Answer: C) Easier said than done.
Answer: A) Move heaven and earth to.
Answer: A) Courage and innovation in facing challenges.
Answer: B) Make every possible effort.
Answer: B) Good enough.
Answer: C) Bite off more than you can chew.
Answer: A) It's not worth the payoff.
Answer: B) KEEP YOUR NOSE TO THE GRINDSTONE.
Answer: B) Couch potato.
Answer: B) Workaholic (be a workaholic).
Answer: C) Pulls out all the stops.
Answer: C) Have a go at.
Answer: B) Going through a lot of effort or trouble to achieve something.
Answer: C) Busy with something.
Answer: B) Made it as good as possible.
Answer: D) Your way.
Answer: C) To make a lot of effort.
Answer: A) Zero waste.
Answer: B) The result justifies the hard work.
Answer: C) Someone who may not get the highest grades but who tries really hard.
Answer: D) Keep your nose to the grindstone.
Answer: C) Burning midnight oil.
Answer: A) There's nothing to worry about.
Answer: B) Hit the books.
Answer: C) Don't give up.
Answer: A) It's a piece of cake.
Answer: B) To contribute to some cause.
Answer: A) Tooth and nail.