1.
twins? — Kim and Kate
2.
Bill's parents? — Sue and Sam
3. Bill's grandparents? — Tom and Beth
4.
Mike's son? — Johnny
5.
Sam's wife? — Sue
6.
Janet's husband? — Mike
7.
Sue's daughters? — Kim and Kate
8.
in their late thirties? — Mike
9.
in his
mid forties? — Sam
********************
1) единственное число или неисчисляемое существительное - is.
2) множественное число - are.
3) I - am,
he/she/it - is,
you, we - are.
There is a chair near my bed.
There are two chairs near my bed.
3. He is my best friend Nick.
4. You are my best friend.