Determining the functions of play is difficult because the functions may be long-term, with beneficial effects not showing up until the animal's adulthood.
定义玩耍的功能是困难的，因为这些功能可能是长期性的，其积极影响要到动物成年后才会显现。
2
Attempts to correlate specific language functions with particular parts of the brain have not advanced very far.
试图把特定的语言功能和大脑特定区域相联系的努力还没有取得很大进展。
《柯林斯英汉双解大词典》
3
The child was not able to speak, walk properly or control bodily functions.