Make sentences in the present perfect affirmative or negative, using these past participles. (done, lost, arrived, built, put , made, changed) 1. i can't find my mobile. i think i it. 2. this isn't right. s mistake. 3. i can't go to bed. i my homework. 4. martin and lizzie are here but jay 5. look! they a little house in the tree. 6. helen the colour of her hair. she looks completely different. 7. you the butter in the fridge. look! it's melting.

1. I can't find my mobile. I think have I lost it.
2. This isn't right. He  has made mistake.
3. I can't go to bed. I haven't done my homework.
4. Martin and Lizzie are here but Jay hasn't arrived.
5. Look! They have built a little house in the tree.
6. Helen has changed the colour of her hair. She looks completely different.
7. You haven't put the butter in the fridge. Look! It's melting.