At first, people raised dogs to help them hunt and to warn them when danger ______ . Today, cats and dogs are kept largely as pets.

A.gaps B. intervals C.length D. distance

A)helped

B)will help

C)are helping

D)will be helping

A)would rather not do

B)shouldn't do

C)shouldn't have done

D)had better not do

A)Would I

B)May I

C)Will I

D)Shall I

A)mustn't

B)can't

C)may not

D)couldn't

A)Will

B)Shall

C)Would you like that

D)Do you want that

A)would rather not to have

B)would rather not have

C)would rather not had

D)would rather that I not have

A)cannot have said

B)might not have said

C)couldn't say

D)must not have said

A)the moment B)for the moment C)at the moment D)in a moment

A)grant B)estimate C)council D)check