【开头句】

1. Today, as a greener means of transportation, bike-sharing is becoming more and more popular in many cities.

2. I am very happy to know that Datang School will start the summer camp. The middle school students from the Belt and Road countries will join it.

3. Do you agree that your parents have a second child? Different students have different opinions about it.

【中间句】

1. There will be less pollution because of bike-sharing. Besides, bike-sharing helps people take more exercise. In this way, it's helpful to people's health.

2. I want to be a cook，because I want to cook delicious food for students and make them know more about our food culture.

【结尾句】

1. As long as we take good care of bikes, it will make our life better and better, and our environment will be more beautiful.

2. I will try my best to let students have a wonderful time in our country.

3. As for me, I'd love to have a brother or sister as company, so that we can share our happiness and sorrow anytime.