how - their task - long - been - doing - have - they? (choose the correct sentence)
A)how they have been long doing?
B)how long have they doing the task?
C)how long have they been doing their task?
D)how long the task have been doing they the task?

Question

Quizplus · Accepted Answer

Option C is the correct formation of the question. It correctly uses the present perfect continuous tense ("have they been doing") and places "how long" at the beginning to ask about the duration of the activity.

How - Their Task - Long - Been - Doing