A man and woman both wearing white , standing on the Great Wall of China .
It is probable that a man and woman smile as they reach the top of the Great Wall of china .
It is highly unlikely that a man and woman smile as they reach the top of the Great Wall of china .
It is probable that a man and woman smile as they reach the top of the Great Wall of china .
A man and woman smile as they reach the top of the Great Wall of china .