当and连用两个或多个单数名词作主语时，谓语动词用单数还是复数通常取决于意思，而不取决于形式。

如果 A and B 或 A, B and C 被视为一个意义整体，其后的谓语动词用单数，若考虑其中的个体（A、B、C三个个体），则其后的谓语动词用复数。下面是一些实例（均来自词典或语法著作），请注意体会：

——用复数动词的实例：

Coal, wood and oil are fuels. 煤、木头和油都是燃料。

Cinnamon, ginger and cloves are all spices. 肉桂、姜和丁香都属于香料。

Bridge, poker and whist are card-games. 桥牌、扑克和惠斯特都是纸牌游戏。

Rain, snow and hail are collectively known as precipitation. 雨、雪和冰雹统称降水。

Football, cricket and hockey are all team sports. 足球、板球和曲棍球都是团队运动。

Paper, plastic and cans are sorted for recycling. 纸张、塑胶和罐子分开归类以便回收。

Silver, gold and platinum are precious metals. 银、金和铂都是贵重金属。

Oxygen, hydrogen and nitrogen are all gases. 氧气、氢气和氮气都是气体。

Slates, tiles and shingles are roofing materials. 石板瓦、瓦和木瓦都是盖屋顶的材料。

——用单数动词的实例：

Drinking and driving has been outlawed. 酒后驾车已被定为违法行为。

Chocolate and mint is a winning combination. 巧克力和薄荷是绝配。

Vagrancy and begging has become commonplace in London. 流浪乞讨在伦敦已变得很常见。

Mince and potatoes is a popular dish in Scotland. 在苏格兰，肉末烧马铃薯是很受欢迎的一道菜。

Research and development is vital to a company's long-term success. 新产品的研发对公司的长期发展是极为重要的。

——有时用单数或复数动词均可：

Twelve and eight is / are twenty. 12加8等于20。

Time and tide wait / waits for no man. 岁月不待人。

Care and understanding is / are important. 关怀和理解是重要的。

Law and order has / have been established. 法律和秩序已建立起来。