  This report describes the details of our approach for the event
dense-captioning task in ActivityNet Challenge 2021. We present a
semantic-aware pretraining method for dense video captioning, which empowers
the learned features to recognize high-level semantic concepts. Diverse video
features of different modalities are fed into an event captioning module to
generate accurate and meaningful sentences. Our final ensemble model achieves a
10.00 METEOR score on the test set.
