highway：我看有個high，以為是高速公路，實際卻是一般的公路。
freeway：免費的路，自然是一般的公路了，實際卻是高速公路，難道國外的高速路不收費嗎？
green joke：黃色笑話。也有說blue joke， dirty joke的。

since we talked about the blue joke,so I'll show you one:

A husband said to his wife, "I will take a photo of your breasts and frame it ."
The wife said to her husband, "I will take a photo of your penisss and enlarge it."


Q:what is the strongest muscle?
A:the tongue—it can raise a woman’s hips.
Q:what is the lightest muscle?
A:the penis—it can be raised by a tongue.