It is ________ that he has been addicted to the drugs and has difficulty quitting it.

As is known to all language learners, the newly learnt words will soon be forgotten unless they are _______ used in everyday communication.

The conclusion _____ the police came to _____ the boss was as much to blame as anyone else for the great fire didn’t satisfy everyone.

Twenty million years ago, Idoho was not the dry place as it is now. ______, it was warm and damp, covered with thick forests.

— Did you remember to give Mary the money you owed her?— Yes, I gave it to her ________ I saw her.