有复数也有单数的,但多数情况下用单数.
牛津高阶英汉双解词典
pizza
/ ˈpiːtsə; ˋpitsə/ n [C,U] Italian dish consisting of a flat (usu round) piece of dough covered with tomatoes,cheese,anchovies,etc and baked in an oven 意大利饼（饼上覆蕃茄、 奶酪、 鯷等,在烤箱中烘制）.
附例句:
a ham and mushroom pizza ◆ Is there any pizza left?
pizza ['pi:tsə]
n.比萨饼
例句:
Hello,I'd like to order a large cheese pizza,please.
喂,我要订一个（份）大的乳酪比萨.
Let's go pig out on pizza.
让我们出去大吃一顿比萨饼吧!
Pizza dough must be knead for five minutes.
做比萨饼的面团要揉5分钟.
