It's very simple. 'Another' is simply the two words 'an' and 'other' written as one word. An+other= another. So, whenever you want to put the 'other' after the article 'a' or 'an', the two words join together to make 'another'. For example: Do you want a drink? I already have one. OK, so do you want another drink? (a + other) or I bought a jacket last week, but it's too small for me. I'm going to take it back to the shop to exchange it for another one. ( a + other) In all other cases, you use the word 'other': Plurals (other people, other countries) Uncountable nouns (other food, other stuff) Singular words preceded by other determiners ( the other bottle, that other man, my other phone etc). I hope that helps.

"Another" denotes one alternative, or additional thing. Examples: "Do you like Elisabeth?" "No, I like another girl." "Do you want to eat here?" "I would like to eat at another restaurant." "Would you mind reading this?" "I would prefer to read another book." "I would like another slice of pie." "Other" often denotes a group of alternative things. Examples: "Do you like Elisabeth?" "No, I like other girls." "Do you want to eat here?" "I don't like it here. I prefer the other places." "Would you mind reading this?" "I don't like this book. Could I take the others, instead?" "I would like things other than pie." Now, you can also say, "the other", which means that you want the alternative between two specific things. "Do you like Elisabeth or the other girl?" "The other girl, Christine." "Do you want this slice of pie?" "No, I would like the other slice; it's bigger." I hope that this made sense.

We use 'other' with plural nouns and uncountable nouns. We use 'another' with singular countable nouns. For example: I want to read other books. I want to read another book. 2015 is different from other years. 2015 is different from another year.

simply use "another" when you have at least a little description of the person and use "other" when you don't have a description or don't want to discuss that person