1. Jack (arrived/has arrived). He's in the living room. 2. Look at the colour of

the water! Something (polluted/has polluted) the river. 3. Scientists (have invented/invented) the digital camera in 1991. 4. We (saw / 've seen) the new Johnny Depp film last night. 5. Why isn't my mobile wotking? - I don't know. I (haven't touched/didn't touch) it. 6. (Did you finish/Have you finished) the washing up? Shall we play cards now?