Put the verbs in brackets in the correct form, present perfect or past simple 1.Where's your key? I don't know.I ....

1. Where\'s your key? I don\'t know.I have lost it. 2. I was very tired, so I lay down on the bed and went to sleep. 3. Mary went to Australia for a while but she\'s back again now. 4. Where\'s Ken? He has gone out. He\'ll be back in about an hour. 5. I did German at school but I have forgotten most of it. 6. I meant to phone Diane last night but I forgot. 7. I had a headache earlier but I feel fine now. 8. They\'re still building the new road. They have not finished. 9. Is Helen still here? No, she has just gone out. 10. The police arrested three people but later they let them go.