1 INTRODUCTION
1.1 Discourse Relation Recognition Task
1.2 Summary of this survey

2 THE PDTB CORPUS AND THE CONLL DATASET
2.1 The PDTB Corpus
2.2 The CoNLL Dataset and Shared Task

3 IMPLICIT DISCOURSE RELATION RECOGNITION BASED ON MACHINE LEARNING
3.1 Lexical features
3.2 Syntactic features
3.3 Contextual features
3.4 Implicit Connectives

4 IMPLICIT DISCOURSE RELATION RECOGNITION BASED ON DEEP LEARNING
4.1 Convolutional Neural Networks
4.2 Recurrent Neural Networks
4.3 Hybrid Neural Network Models
4.4 Attention Mechanism
4.5 Neural Learning of Argument Pair Interaction

5 DATA EXPANSION BASED ON SEMI-SUPERVISED LEARNING
5.1 Data Expansion from Explicit Discourse Relations
5.2 Data Expansion from Multi-Language Data
5.3 Joint Data Expansion and Model Training

6 PERFORMANCE COMPARISON

7 CONCLUSION AND DISCUSSION