truth,lie,greeting可数不可数

这三个词都可以加s
truth
that which is true 真相; 实情; 真实情况; 事实: the whole truth 全部事实 * the search for (the) truth 调查事实真相 * tell the truth, ie speak truthfully, not lie 说实话 * We found out the truth about him. 我们了解到了有关他的事实. * The (plain) truth is, I forgot about it. 老实说, 我忘了.

lie
tell a lie 说谎

greeting
1表示普通的问候,致意,打招呼时,不可数
She waved a friendly greeting她友好的打招呼
2.表示祝词,贺词,或给某人教正式的问候时,可数
brithday greetings 生日祝词
My mom sends her greetings to us.我母亲向大家问好(这里要注意哦,较正式的)