A lecture about English
A linguistics professor was lecturing to his English class one day. "In English," he said, "A double negative forms a positive. In some languages, though, such as Russian, a double negative is still a negative. However, there is no language wherein a double positive can form a negative."

A voice from the back of the room piped up, "Yeah, right."

100 Camels
As US tourists in Israel, a man and his wife were sitting outside a Bethlehem souvenir shop, waiting for fellow tourists. An Arab salesman approached them carrying belts. After an impassioned sales talk yielded no results, he asked where they were from. 'America,' the husband replied.

Looking at her dark hair and olive skin, the Arab responded, 'She's not from the States.'

'Yes, I am.' said the wife.

He looked at her and asked, 'Is he your husband?'

'Yes,' she replied.

Turning to the husband, he offered.... 'I'll give you 100 camels for her.' The husband looked stunned, and there was a long silence. Finally he replied,' She's not for sale.'

After the salesman left, the somewhat indignant wife asked her husband what took him so long to answer, to which the husband replied, 'I was trying to figure out how I'd get 100 camels back home.'