Yesterday evening, when I went to town with my 1, we met a strange old man. It was raining 2and we had no umbrella. We were trying to get into a taxi when he came up to us. He was carrying a nice 3 and he said he would give it to 4 for only one pound. He said he had 5 his wallet and he needed taxi fare(费用) to go back home. My mother didn't believe 6 he said at first, and asked him a lot questions. but she finally believed the man and gave him a pound. She was 7 to buy a good umbrella for so little. but the old man didn't get into a taxi. We followed him and found he went into a pub(酒吧) and bought 8a glass of whiskey(威士忌) with a pound. 9he drank it, he put on his hat and took one of the many wet umbrellas there and went off with the new one. Soon after that, he 10 it again.
菌的DNA＋DNA酶→加入R型菌→注射入小鼠