Amazon Comprehend is a natural language processing (NLP) service that uses machine learning to discover insights and relationships in text. Starting today, Amazon Comprehend training and inference batch jobs now supports Amazon Virtual Private Cloud (VPC). With VPC support, your batch jobs and the AWS resources they access, such as the Amazon Simple Storage Service (S3) buckets can be made private within your network and not connected to the internet. This enhancement also enables you to monitor all network traffic in and out of your batch jobs, using VPC Flow Logs.
from Recent Announcements https://aws.amazon.com/about-aws/whats-new/2019/05/amazon-comprehend-batch-jobs-now-supports-amazon-virtual-private-cloud/