Now this is hard. I know that is used to be the case that the apostrophe was used in the place of an omission of other letters, i.e. it is However it is also used in possession, or is it? Nowadays we have ceased using one of these, I presume it is (?) the former case here. Apostrophe is still used for possession as far as I know. Is it now ungrammatical to use apostrophe for the omission of letters as once it wasn't? e.g. It's going to take a long time. Or do I have the wrong end of the stick completely?