This is____ a difficult problem ____ all of us can’t work it out.

I’m so sorry that you didn’t win the skating marathon.－How long _____ you ______?－I skated for 5 hours.

Daniel is a good student. He ____ Chinese and Maths.

This book is ______,I like it very much.

People ______ the west often celebrate Halloween ______ many ways.[ ]