my $pest    = 'flea';
       $dog     = \$pest;
       $cat     = \$pest;
       $bob     = \$dog;
       $sue     = \$cat;
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• $pest ___(1)___ 'flea'
• $dog is a reference to $pest
• $dog ___(2)___ 'flea'
• $bob is a reference to $dog
• $bob is a ___(3)___ to $pest
• $bob ___(4)___ 'flea'
• 'flea' is the value of the variable $pest
• $pest is the ___(5)___ of $dog
• 'flea' is the ___(6)___ of $dog
• $dog is the ___(7)___ of $bob
• $pest is the ___(8)___ of $bob
• 'flea' is the ___(9)___ of $bob
• 'flea' is the ___(10)___ of $dog
• $dog and $cat are ___(11)___ {~similarity}
• $bob and $sue are ___(12)___ {~similarity}

only what to call stuff when speaking English to you

You're ask for what I would say, but you provide sentence structures I wouldn't use. I would say:

1. The pest is a flea
2. The dog has fleas
3. Bob's dog's pest
4. Bob's dog has fleas
5. The pest of the dog
6. Fleas have infested the dog
7. The dog is owned by Bob
8. The pest of Bob's dog
9. Fleas infest Bob's dog
10. Fleas infest the dog
11. The dog and the cat have fleas
12. Bob's and Sue's pets have fleas

You, on the other hand, might say,

1. $pest is 'flea'
   $pest contains 'flea'
   $pest holds 'flea'
   $pest's value is 'flea'
2. [ $dog has no direct relationship to 'flea' ]
3. [ $bob has no direct relationship to $pest ]
4. [ $bob has no direct relationship to 'flea' ]
5. $pest is the referenced by of $dog
6. [ 'flea' has no direct relationship to $dog ]
7. $dog is the referenced by of $bob
8. [ $pest has no direct relationship to $bob ]
9. [ 'flea' has no direct relationship to $bob ]
10. [ 'flea' has no direct relationship to $dog ]
11. $dog and $cat are equal
12. $bob and $sue are both lexicals containing a reference