Penelitian ini bertujuan untuk menginvestigasi tipe-tipe dan sumber interlanguage yang dinuat oleh siswa-siswa kelas X di SMKN 1 Singaraja dalam menulis teks deskriptif. Keseluruhan data dianalisis menggunakan teori dari Azar dalam mengklasifikasikan tipe-tipe eror yang dibuat oleh siswa. Berdasarkan data dari analisis penelitian ini, terdapat 14 tipe eror yang dibuat oleh siswa yang termasuk: verb tense (16.61%), capitalization (14.70%), omit a word (11.50%), add a word (10.86%), singular-plural (8.31%), run-on sentence (6.39%), word choice, word order dan spelling (5.75%), punctuation (4.79%), word form (3.51%), article (2.56%), meaning not clear (1.92%), dan yang terakhir yaitu incomplete sentence (1.60%). Berkaitan dengan sumber-sumber eror, hasil dari penelitian ini mengindikasikan bahwa sumber terbesar dari eror adalah communication strategy (46.33%)Kata Kunci : teks deskriptif, interlanguage, tulisan This research aimed at investigating the types and sources of interlanguage committed by the students of class X in SMKN 1 Singaraja in writing descriptive text. All data were analyzed by using Azarâs theory in classifying the types of error committed by the students. Based on the analysis of this studyâs data, there were 14 types of errors committed by the students, which includes: verb tense (16.61%), capitalization (14.70%), omit a word (11.50%), add a word (10.86%), singular-plural (8.31%), run-on sentence (6.39%), word choice, word order and spelling (5.75%), punctuation (4.79%), word form (3.51%), article (2.56%), meaning not clear (1.92%), and the last was incomplete sentence (1.60%). In terms of error sources, the result of this study indicated that the major source of errors was communication strategy (46.33%).keyword : descriptive text, interlanguage, writing
                        
                        
                        
                        
                            
                                Copyrights © 2017