stomach-stomachs，a German-three Germans, an American-two Americans，man cook - men cooks;

papers 报纸, 文件manners礼貌drinks饮料in a word 简言之?

in other words 换句话说have words with 与某人吵嘴

have a few words (a word) with sb.与某人说几句话

The crowd were running for their lives. 某些集体名词, 如people, police, cattle等,

只当复数看待, 谓语动词必须用复数。

The police are searching for him.