suffix

In the word 'happiness', the suffix '-ness' changes the adjective into a noun.

(Chinese) 在“happiness”这个单词中，后缀“-ness”将形容词变成了名词。

The suffix '-ed' is used in English to form the past tense of regular verbs.

(Chinese) 后缀“-ed”在英语中用于构成规则动词的过去式。