1. A small child has to learn to keep its ________（平衡）before it can walk far.
2. Christmas is an ________（每年的）festival for most of the people in the world.
3. As a new teacher，Susan tried to ________ (促进)good feelings between students and her.
4. Everything falls towards the center of the earth because of the pull of ________ （重力）.
5. He couldn’t ________ (适应) his way of life to the company.
