stay

1.Will you stay dinner here? （你肯留在这里用膳吗）和We shall stay the night in the cottage（我们将在这小屋里过夜）两句里的stay都合乎习惯。

2.He stayed to dinner（他留着等待用膳）和He would not stay to the wedding（他不肯留着等待婚礼）等句子里的to改用for也可以，也可以省去，参见1

3.stay at home比stay home正式。

4.stay put（停留着、不移动）原来是美国英语，put是过去分词。stay后面接其他过去分词似乎只用在美国。例如：The matter is now considered settled, but I am afraid it will not stay settled.