THOUGH MY FATHER WAS VERY TIRED, HE WENT ON ... .A. WORKB. TO WORK...

31. - 3500 CAU TRAC NGHIEM ON TAP AV THCS
3500 CAU TRAC NGHIEM ON TAP AV THCS

31. Though my father was very tired, he went on ... .

a. work

b. to work

c. working

d. worked

 c