程度副词：比较、更加，还、相当

These are adverbs used to add a degree to adjectives or verbs. '比较' (fairly) is used for mild comparison, showing a relatively high but not too strong degree, e.g.: '我比较喜欢游泳' (I rather like swimming). '更加' (even more) emphasizes an increased degree compared to before or to something else, often used with '了' to indicate a change, e.g.: '她以前学习就很努力，现在更加努力了' (She used to study very hard, and now she studies even harder). '还' (still/a bit more) is used in comparisons to indicate a slightly greater degree, e.g.: '这个房间不干净，那个房间还干净一些' (This room isn't clean, that room is a bit cleaner). '相当' (quite/very) emphasizes a very high degree, almost equivalent to '很' but with a stronger estimative tone, e.g.: '这个公园的景色相当漂亮' (The scenery of this park is quite beautiful).