Question

change the voice . 1) why could not they complete their assignment in time? 2)They have not been doing their work since morning.​

Answer 1

Hey!

Here's your answer....

1. Why wasn't their assignment completed

in time by them.

2. Their work had not been done by them

since morning.

Answer 2

Answer:

1) Why their assignment could not be completed in time by them ?

2) You can't do it. Because voice can't be changed in present perfect continuous tense.