Billy leaned forward and brushed a speck of dust off his shoes.比利俯身擦掉了鞋子上的一丝灰尘。I've got a speck of dirt on my shirt.我的衬衫上有一点污垢.Not a speck of cloud is to be seen.看不到一星星云丝....

a speck of的音标：a speck of的英式发音音标为：[ə spek ɔv]a speck of的美式发音音标为：[e spɛk ʌv]...

一点点...