xué xí / zhōng wén / shí / zhǎng wò / dì sì shēng / de / fā yīn / duì / chū xué zhě / lái shuō / bǐ jiào / kùn nán

学习中文时，掌握第四声的发音对初学者来说比较困难。

When learning Chinese, mastering the pronunciation of the fourth tone is relatively difficult for beginners.