addition的形容词形式是additional；
addition
n.加;加法;增加物;添加物;增加;添加；
复数： additions；
例句：
The addition of flour will thicken gravy.
加了面粉肉汁会变稠。
相关介绍
There is, in addition, one further point to make.
此外，还有一点要说。
Pasta's basic ingredients are flour and water, sometimes with the addition of eggs or oil.
意大利面制品的主要成分是面粉和水，有时加鸡蛋和食用油。
In addition to these arrangements, extra ambulances will be on duty until midnight.
除了这些安排以外，另增救护车值班至午夜。
