與介詞to搭配，表示作用於，例如：
1、A bird's wings are comparable in function to a fish's fins.鳥的翅膀與魚的鰭功能相似。
2、It was her first time to visit the Chinese city， and she said that it was also her first time to use the app's online payment function to pay for the ride.這是她第一次訪問這座中國城市，她說，這也是她第一次使用該應用的在線支付功能支付乘車費用。
3、Periscope， an app for smartphones， uses a video function to allow users to stream events scope是一款智能手機軟件，用戶可以使用視頻功能記錄生活中發生的點滴。
