我如何更新这 52 个包？
我给了一个sudo apt-get update，但一切仍然存在。
Welcome to Ubuntu 16.04.5 LTS (GNU/Linux 4.4.0-138-generic x86_64)
* Documentation: https://help.ubuntu.com
* Management: https://landscape.canonical.com
* Support: https://ubuntu.com/advantage
Get cloud support with Ubuntu Advantage Cloud Guest:
http://www.ubuntu.com/business/services/cloud
52 packages can be updated.
9 updates are security updates.