The mountains form a natural            between the two countries so they have no trade relations in history.

 You are really very kind. I’ll never forget the      you have done to me.

Some famous singers live on the ___ from their record sales.

It struck me like a blow when I saw his ___________ on the legal document which sold our house to another family.

The system has been designed to give students quick and easy _________ to the digital resources of the library.