我今天试图更新我的软件包：
$ sudo apt-get upgrade
Reading package lists... Done
Building dependency tree
Reading state information... Done
You might want to run 'apt-get -f install' to correct these.
The following packages have unmet dependencies:
linux-headers-3.16.0-44-generic : Depends: linux-headers-3.16.0-44 but it is not installed
E: Unmet dependencies. Try using -f.
所以，我继续尝试apt-get -f install：
$ sudo apt-get -f install
Reading package lists... Done
Building dependency tree
Reading state information... Done
Correcting dependencies... Done
The following extra packages will be installed:
linux-headers-3.16.0-44 …