Our maths teacher set so difficult an examination problem ______ none of us worked out.

The chief manager has decided to put _____ he thinksis energetic, clever and capable to the position of the leadership of thecompany.

Jeremy Lin __________ an unknown basketballplayer in New York Knicks for quite a long time.

Mike finds reading English newspaper_______, because there are lots of new words.

We are happy to know that our head teacher will be _____ to headmaster.