We can have ___ bluer sky if we create ___ less polluted world.
How about_________out for a walk,mum?
--- I think English is very useful.--- . And we must learn it well.A. I agree with youB. I don't think soC. It's nice of you
--- do you want to be when you grow up?--- I want to be a pilot and fly in the blue sky.A. Which B. Who C. What
--- It is very cold this winter.---Yes, but it was colder last winter, I remember.A. already B. even C. more
I think _ is impossible for me to climb such a high mountain.A. it B. this C. that