Wrong way

An old man called Albert was driving down the M4 motorway, when suddenly his mobile phone rang. It was his wife.

She said, "Albert, listen to me. I've just heard on the news that there's an idiot driving his car the wrong way down the motorway. So, please drive carefully, do you hear me?"

"OK dear," said Albert. "I'll try. But it's not just one car. There are hundrends of them!"