Doctors Without Boarders, ________ international organization, received ________ Nobel Prize for Peace in 1999 for its outstanding work .

It’s cold outside. You’d better yourcoat.

It was with great joy _______ he worked out theproblem that he had long been puzzled about

A lot of fish in the river _______ recently, because there is lots of pollution.

It is in the hotel _____ he stayed last night ______ he lot his mobile phone.