My book isn’t on my desk. Where _______ I have put it?
_______ was known to them all that William had broken his promise ______ he would give each of them a gift.
The ___ look on his face showed that he hadn’t expected it .
___ from space, the earth with water ___70% of its surface looks like a "blue blanket".
____ more attention, the trees could have grown better.
Someone is ringing the doorbell. Go and see ______ .