The meaning of either a, b, c, or d is from this answer sort of clear in that it means. Morris 37 ― either twilight and the day between Either should know how to open the door means whichever you should happen to come across, he will know how to open the door
Jameliz S aka Jelly Bean Brains Age, Real Name, and Wikipedia - Loot
Of course this suggests that they both know, but it's not the same as saying that they both know
The suggestion is that you will only encounter one, and that he will know (maybe he will be told at the last minute).
There are two common pronunciations of either British /ˈaɪðər/ and american /ˈiːðər/ If americans are more or less consistent in this regard, then the brits seem to be freely using both The word either is derived from the old english ǣgther, which was a short for contracted form of ǣg (e)hwæther, of germanic origin
Either is used where one is required and there are multiple options, usually two It can be used for more than two but it is most often is used for only 2 options. It says that it is informal to use either on more than two options, but is used widely especially in oral communication However, he didn't mention that what is the best alternative to either in three or more options in formal context, and hence i posted this question here.
In fact, does either of you and do either of you are both used by native english speakers
But if the subject isn't either of you, you should use a singular verb with either of. The use of either is fine, but not in the way it's currently used It should really be …, with no fruit borne from either (of the two) In other words, the phrase, essentially, needs to be reversed.
Either of these options does work for me Either of these options do work for me Wrong the first is the correct form, as you suspected But do either of these options work for me? would be common in casual speech
This is a difficult rule even for native english speakers.either of, one of, etc.
