S is daughter of P and sister of T. So, T is daughter of P. 

Now, the sister of P is the daughter of M. This means that P is also the daughter of M. Clearly, T is the granddaughter of M. 

So, M is the Grandfather or Grandmother of T. 

Q, the Doctor, is the father of T. S, the Housewife, is the grandmother of T and hence the mother of Q. Since there are only two married couples one being that of Q, the grandfather of R. i.e, U must be married to S. Thus, R and T will be both children of Q and these must be the students So, P, who remains, shall be the wife of Q and she alone can be the nurse. Thus, U must be the contractor 

Clearly, R and T are children of same parent, So. R will be the sister of T. 

My father's brother's only sibling is my father. My father's mother is my grandmother. My sister's only brother is myself. So she is my Grandmother.

Clearly, the lady is the grandmother of man's sister's son i.e.. the mother of the mother of man's sister's son 

i.e., the mother of man's sister. So, the lady is man's mother.  

A is the father of X and Y is the sister of X. So, Y is the daughter of A.

C is the daughter-in-law of A who is the grandmother of F means C is the mother of F But F is the son of B. 

So. B is C's husband. But C, the lawyer. is married to the Doctor So. B is the Doctor. F. the Accountant, will he the non of B and C E is the unmarried Engineer 

So. the other married couple can be that of grandmother of F. i.e, A and D. But D, the Salesman, is married to the Lady Teacher. 

So. D, the Salesman, is the grandfather of F. father of B and the husband of A. the Lady Teacher. 

A is the Lady Teacher