Many people like spring, because they can go out and do many kinds of activities. We made a survey about the activities that people like to do in spring. Here are the results.
Scott：
In spring, I often visit my uncle and I like fishing with him. I also like boating and enjoy the beach. Last spring my uncle and I went boating. The dolphins came so close to us. It was very amazing. I hope that I can go there again soon.
Linda:
My favorite spring activity is gardening (园艺). I think it is relaxing to work in the garden. I grow many flowers in my garden every year. They are so beautiful.
Nancy：
I love spring. I love going to the beach and spending a whole day there. It is so relaxing to lie on the beach. I also like surfing in the sea.
James：
I am twelve years old. My favorite spring activity is swimming. I started to learn swimming when I was seven years old. I always have a good time with my friends in the river.
。若该种群植物自交，后代中AA、aa基因型个体出现的频率以及A、a基因频率分别为