How to use suggest in elasticsearch

Elastic Stack Elasticsearch
1

Hi,

how to get the suggest in elastic search. Using curl post method and php.

when i search with first three letters it have to show the city start with three letter i had typed.

Below is my code

cities/city/_suggest?pretty=true&size=".$size."&from=".$from;
{
   "city-suggest":{
      "text":"atl",
      "term":{
         "field":"city"
      }
   }
}

Thanks