Appending string at the end of url in GET method :Volley

StringRequest strreq = new StringRequest(Request.Method.GET,
     "https://sample.com/testing" + Hear Your dynamic value,
      new Response.Listener() {
         @Override
         public void onResponse(String Response) {
                  // get response
         }
      }, new Response.ErrorListener() {
         @Override
         public void onErrorResponse(VolleyError e) {
            e.printStackTrace();
         }
});
Volley.getInstance(this).addToRequestQueue(strreq);