In this task, you're given an article and an answer. Your task is to generate the fill-in-the-blank question for this answer based on the given article. The blanks are always at the end of the question, and can be filled with more than one word or phrase.

Article: According to Hunan Daily, in Yongxing County of Hunan Province, retired teacher Chen and his wife are living in a natural cave , and they quite enjoy such life. [:Zxxk.Com] Chen's cave is 20 meters wide and 8 meters deep. Lichens can be seen everywhere in it. Chen says that the place is free of pollution. Because of being poor, they moved into the cave, Chen said. In 1975, the houses of his families and his neighbors were all burned to the ground in the fire. Chen was then already married and badly needed a house to live in. But he had no money to build a house, so he had to live in his relatives' houses as long as 5 years. In 1980, he happened to discover this cave, immediately he and his family members decided to live in there. Chen thought the cave could be a temporary living place, but it never occurred to him that it could be his home in the next 28 years. Chen recalled that the first couple of days were the most difficult period, "I put up some wooden boards for a gate, but they were all blown away by wind that same night." Chen has two sons and a daughter, and they all left the cave after they got married. Now Chen's old friends once in a while visit him in his cave drinking and playing Chinese chess. For Chen, the most enjoyable thing is to raise bees and grow kinds of plants.
Answer: raising bees and growing plants
From the passage we know what Chen likes to do most is _ .