Tìm lỗi sai trong câu sau: What do you go to school?

Tìm lỗi sai trong câu sau: 
1. What do you go to school? - By bike.
2. Mount Everest is the higher than mountain in the world.
3. Would you like any cereal? - Yes, please
4. Ellie didn't finisher her homework last night
5. they had a birthday party two day ago