what is mouth-watering??

Food, of course. Food that makes your mouth water. 流口水。

當我們看到賣相很好的食物，總會垂涎三尺，有很想吃的衝動，可以這樣形容：That looks so mouth-watering.（它看起來很好吃的樣子），也可 ... That looks so mouth-watering. 坎迪斯：看看這道菜，它看起來很好吃的樣子。 Katherine：I don’t think so. ...
www.chinapress.com.my/topic/english/default.asp?art=1201eg01.txt - 124k -

2006-11-28 19:53:35 補充：
MeaningDelicious; tasty enough to make you salivate.

2006-11-28 19:54:41 補充：
The term mouth-watering has been used since the late 18th century to describe people whose mouth was salivating at the thought of food.

2006-11-28 19:54:52 補充：
The earliest citation that I can find of it describing appetizing food itself is from the mid 19th century, in the US fine arts journal The Southern Literary Messenger, 1847:

2006-11-28 19:56:36 補充：
"He talks in an unctious mouth-watering way of British oysters and Falernian wine."from phrases.org.uk

.The roast mutton on a stick is mouth-watering.
(烤羊肉在柴枝上味道是很好的)