How to combine two array list and show in a listview in android

I want to combine two ArrayList into a single one.

My first arraylist looks like this:

{a,s,d,f,g,h,......}

My second arraylist looks like this:

{z,x,c,v,b,.....}

Then I want to combine both to be as

  {a,s,d,f,g,h,.....,z,x,c,v,b.....}

First List is

ArrayList<String> firstname1   = new ArrayList<String>();

Where as the second list is as

ArrayList<String> first   = new ArrayList<String>();

Now I want to combine all this together and I want it to be listed out in list view. How to do this?