Hi there, I'm finding it difficult to pick when to use 's and s'. I researched it online and it seems that you only use 's or s' when you are noting possession of something (or you mean "it is"), and you use s' when the possession is of something that is plural? Anyway, I have an essay that I've written and I've been trying to properly ascertain if my grammar is correct. I was wondering if some of you could kindly offer me some help. The development plan is of the school (possession) and there is only one school so should it be school's? The questioning belongs to the teacher, and there is only one teacher. The learning of the students (possession) and it is ALL of the students (plural). I'm not sure about this one. It was the teachers who interviewed so is there possession or is this not the case because this is past tense? Is it teachers' because there are a group of them or just teachers because there is no possession? The homework belongs to the others. Since "others" is more than one (plural) so is would be others'? I am finding these concepts really difficult to grasp so some clarification of the above examples would be fantastic. I'm a student maths teacher and grammar isn't my best area although I do try to use correct grammar when possible. Thank you.