动词填空。
Two men were traveling in a lonely part of America. For days they 1___________ (not see) even a house,
only a few wood huts (木房子). Then one day they 2____________ (meet) an old Indian. They hoped that
they could use their own language 3____________ (talk) with him. One of them had a little conversation with
him and asked him, "Could you tell us what the weather 4____________ (be) like in the next two days?"
"Oh, yes," he said. "Rain 5____________ (come), and so is wind. Then there 6____________ (be) a heavy
snow for two days, but after that the sun will be shining brightly."
"Isn't that wonderful?" said the man to his friend. "These old Indians 7____________ (know) many of the
secrets of Nature than we do with all our science." Then he 8____________ (turn) to the old man. "Tell me
how you 9___________ (know) all that."
"It 10_____________ (hear) over the radio this morning." The Indian answered.
平衡无关的因素（）