ɪɾ ɪz dᵻvˈaɪdᵻd ˌɪntʊ ˈeɪtiːn sˈɛkʃənz kˈɔːld jˈuːnɪts, wˌɪtʃ ɑːɹ jˈuːnɪt wˈʌn,tˈuː,θɹˈiː,fˈoːɹ,fˈaɪv,sˈɪks,sˈɛvən,ˈeɪt,nˈaɪn,tˈɛn,fˈɪftiːn,sˈɪkstiːn,sˈɛvəntˌiːn,twˈɛnti,twˈɛnti wˈʌn,twˈɛnti θɹˈiː,twˈɛnti fˈoːɹ ænd twˈɛnti fˈaɪv.
It is divided into 18 sections called Units, which are Unit 1,2,3,4,5,6,7,8,9,10,15,16,17,20,21,23,24 and 25.