Here you can generate a list of subdomains with particular masks for the domains based on rules and lists. This tool supports four sets of "words" that can be used in your input.
Let's generate subdomains like dev.admin.google.com. To do that, you need to enter as input: $1.$2.google.com. $1 and $2 are the sets that you can change.
It will generate all combinations based on $1, $2 and, as a result, you will get the following list:
You can change any of the sets with any data you want. You can also use each set as many times as you wish - like $1$1$1, $1$2$2$3$4, etc.