_______ with so much trouble, we failed to complete task on time.
When we were young, every evening my brother and I____ stay at home waiting for our mother.
We arranged to meet at 8:00, but she never ______.
Missing the flight means _______ for another three hours.
After I had finished eating, he advise me ______ immediately.
-----This returned Chinese scholar has become one of the top experts in this field.-----Yes, I know him very well. He _____ in Africa with wild animals for eight years.