POSSESSIVE or PLURAL?

 When a noun   has something that belongs to it, we usually make it possessive by  adding an    APOSTROPHE and an S.  ('s)

the dog's bone
the teacher's book
the student's  pencil case
my grandmother's recipe    /   Grandma's recipe
the neighbor's yards

For plural nouns, add the apostrophe after the s:
the dogs' bones
the teachers' books
the students' pencil cases
our  grandmothers' recipes
the neighbors'  yard

When a plural noun ends in  /es/ :
class (singular)  - class's
classes (plural) -   classes'

Singular and Irregular plurals:
the  lady's shoes         --        the ladies' shoes
a child's toys                 __       the children's toys
a woman's clothing       __        women's clothing

When a singular noun ends in  /s/ we usually add an 's:

Mr. Jones's car
this class's   students
the bus's driver

 BUT we can also   write it like plural nouns:
Mr.    Jones's car  / Mr.  Jones' car
The plural of Jones is Joneses. , so the possessive is Joneses'
class's students  / class' students
the plural of class is classes, so the possessive is classes'

POSSESSIVE  or PLURAL?
1)   These computer__ are old.
2)   Are you Richard__ uncle?
3)   Alfred has two sister__and  two brother__.
4)   My dog_ name is Lolita.  What's your dog__ name?
5)   This is Tom__ bike. 
6)   Do you work at the butcher__?
7)   When she goes to Mexico, she stays at her grandparent__ farm.
8) Piero__cousin__ live in  Leghorn. 
9)   Sarah visits her   relative__ often because her  cousin__  yard is enormous!
10)   Is that your phone? No, it's Heather__.
11) Whose bags are these? They're those men__ over there.
12)   I buy donuts at the baker__ every morning before school.
13)  Betty__ feet are the smallest in the class.
14)   Our class__ windows are open.
15) The school__ cafeteria is  not very big.