additional layer of felt

例句：

1. 1. The additional layer of felt is necessary for the project to be completed smoothly.
   额外的一层毡是项目顺利完成所必需的。
2. 2.We need an additional pair of shoes for our trip.
   我们需要一双额外的鞋子来我们的旅行。
3. 3.The additional information will help us understand the problem more clearly.
   额外的信息将帮助我们更清楚地理解这个问题。