302. The two countries once into one, it will become a strong and powerful one in the world.
In the past we lost many chances, _______ we paid little attention.
The pen, _______ I had been writing for ten years, was broken.
Mary has two brothers, ________ are doctors.
The problem _______ you argued about yesterday has been solved.
My aunt bought me a book, the name _______ I have forgotten.