a cotton mill的用法和样例：
- Cotton cloth is made in a cotton mill.
- A cotton mill often average up the various grades of cotton to produce a fairly uniform yarn.
- He wrote a meritorious theme about his visit to the cotton mill.
- There is much mythologizing surrounding Zhang's rise to prominence, given that his first job was as a farmhand and then a laborer in a cotton mill.
- She works at a cotton mill.
- A pilot study(5 m~3/d) was conducted for the advanced treatment of secondary effluent from a cotton mill by using the biological aerated filter(BAF)/ultrafiltration(UF)/reverse osmosis(RO) process.