ad. (非正式)是, 是的
在线英汉词典

yeah的短语、例句：

yeah adv (infml 口) 1 (casual pronunciation of) yes *yes（的俗音）. 2 (idm 习语) ,oh `yeah? (used to show that one does not believe what has been said 用以表示对所说的话不相信)
`I´m going to meet the Prime Minister.´ `Oh yeah? Very likely!´ ｀我要去见首相了.＇｀噢, 是吗? 那太有可能了!＇