Who can _____that he finished his task alone?

Look! The man _____ the black car is my son’s teacher. [ ]

It is well known that nature has provided Shangri-la(香格里拉) with endless natural treasures, making the land happy home for the local people．

Emma,come here,please. Heresome newspapers for you.

Do you have any idea ______ on earth has happened to our friend?