翻译:对中国学生来说,英语中的双元音(diphthong)很难掌握。
For the Chinese students that the diphthong of the English is problematic .
参考翻译:English diphthongs are particularly problematic for Chinese students to master
造句:西游记中师徒四人西天取经真是困难重重。
In the Journey to the west learn from the west has been problematic for the four mentoring.
形容词:困难重重