Before revision:  We add two pre-training tasks as the auxiliary task into dependency parsing as multi-tasking , which improves the performance of the model in both in-domain and  cross-lingual aspects.
After revision:  We add two pre-training tasks as the auxiliary task into dependency parsing as multi-tasking . Assuming only unlabeled data from target languages plus the source treebank can be exploited together, we adopt a self-training strategy for further performance improvement in terms of our multi-task framework. Our proposed cross-lingual parsers are implemented for English, Chinese, and cross-lingual aspects.