Question

playing
(d) play
14. By evening, we .... ........... 20 kilometers.
(a) walking
(b) has walked (c) had walked (d) walks
15. If you .....
...... hard, you would have passed.​

Answer 1

The correct answers are had walked and had worked.

• The blanks are filled as such:  By evening, we had walked 20 kilometres. If you had worked hard, you would have passed.

• In these blanks, past participles of verbs are used with the addition of had exhibited that these sentences are of past perfect tense.
  

• These sentences are also known as pluperfects.