Present Perfect and Simple Past

Where __________ that robot vacuum cleaner?

• did you buy

• have you bought

I __________ a great program about robots on TV last night.

• watched

• have watched

_________ you ever seen a robot dance?

• Did

• Have

In what ways _________ robots influenced our lives?

• did

• have

Technology such as cash machines _________ our lives more convenient.

• have made

• made

In 1996, world chess champion Garry Kasparov _________ the computer Deep Blue at chess

• beat

• has beaten

What jobs _________ machines already taken?

• did

• have

Scientists _________ "narrow intelligence" for robots so far -- only humans possess "general intelligence"

• developed only

• have only developed