We have seen photographs of the whole earth taken from great distances in outer space. This is the first time, the (1)...first time, in man's long history that such pictures have been possible. (2)...many years most people have believed that the earth ws ball-shaped. A few thought it was round and (3)..., like a coin. Now we know, beyond doubt, that those few were(4).... The photographs show a ball-shaped (5)..., bright and beautiful. In colour photographs of the earth , The sky is as (6)...as coal. The(7)...looks much bluer than it usually does to us. All our grey(8)...are a perfect white in colour; because, of course, the(9)...is for ever shinning on them. we are (10)...to live on the beautiful earth.