用所给动词的适当形式填空。 1. Hello, I _____ (not know) you _____(be) in London. How long have you been there? 2. By the end of last week, he _____(read) this book four times. 3. I _____ (not have) any English knowledge before I came here. 4. I _____(lose) my keys. I can't remember where I last saw them. 5. -_____you _____ (see) the film yet'? -Yes, I _____(see) it last week.