1. He __________ back a month ago. (come)
2. My mother often tells me __________ in bed. (not read)
3. I must take it back the day after tomorrow. You can only __________ it for 24 hours. (keep)
4. Why have you kept me __________ here for so long a time? (wait)
5. Please come to our meeting if you __________ free tomorrow. (be)
6. She __________ to the Great Wall several times. (go)