Without facts, we can’t form a correct opinion, for we need to have actual knowledge _______ our thinking.

John is the only one of the students in the class that never _______ a mistake even when it is pointed to him.

We aretaught that a business letter should be written in a formal style ____ in apersonal one

___________ you are， ____________ mistakes you’ll make.

Although I try to talk to my classmates, I still find _____ hard to make good friends with them.