The drivers are repairing their cars
The drivers are repairing their cars, aren't they?
Are the drivers repairing their cars?
Are the drivers or teachres repairing their cars?
Who is repairing their cars?
What are the drivers repairing?
The scientist would like to catch this butterfly
The scientist would like to catch this butterfly, wouldn't they?
Would the scientist like to catch this butterfly?
Would the scientist or the driver like to catch this butterfly?
What would the scientist like to catch?
Who would like to catch this butterfly?
Charles has just finished his translation
Charles has just finished his translation, hasn't he?
Has Charles just finished his translation?
Has Charles orf Dennis just finished his translation?
What has Charles just finished?
Who has just finished his translation?
They haven't discussed the problem yet
They haven't discussed the problem yet, have they?
Have they discussed the problem yet?
Who has discussed the problem yet?
What have they discussed yet?
Have they or we discussed the problem yet?