Create method parse that outputs strings that belong in a List

Question

I want to create a class Parser i.e.

public class Parser{
   List<String> lines;

that has a method parse which takes in a list of lines as an input and outputs all the strings (one string in each line) in the list i.e.

public String parse(List<String> lines){

For example, if my list has: List lines = Arrays.asList(new String[]{"one", "two three"})

my output for Parser.parse(lines) will be

one
two three

May I get some help with the method parse?