What should I use? When you ask a person to choose only one kind of thing. Which one do you like? apples, candies or cookies? or Which ones do you like? apples, candies or cookies?
Why is a just a rather odd wh -word. Its distribution is very limited -- it can only have the word reason as its antecedent, and since it's never the subject it's always deletable. Consequently it behaves strangely, as you and others point out.
So, why does she ever tweet with standard capitalization (and do so quite randomly and quite frequently)? In contrast to the other answers, my answer (typing in only lower case is simply faster) explains the above tweets quite simply:
mic: The "Please Do Not Swear on My Profile Thanks" meme going viral on Facebook, explained
The "Please Do Not Swear on My Profile Thanks" meme going viral on Facebook, explained
"Ones" is the plural of "one". Example: Are those the ones you are looking for? "Ones" is also the possessive form of "one" when "one" is used as a pronoun. There is no apostrophe, similar to "his". Example: One should mind ones own business. "One's" is a contraction of "one" and "is", or "one" and "has". Examples: One's less than two. One's been less then two forever. If one is used as a ...
What is the proper way to use "ones" or "one's" this word in sentence?
Some people say a dog=one, dogs=ones, the dog=the one=that, and the dogs=the ones=those. It's a rule of thumb, but what I found was that this is not always correct.