我认为英语比日语简单:I think English is ---- ----- than Japanese.

much easier
更准确的翻译是我认为英语比日语简单得多
easy,以辅音字母+y结尾,要把y变i+es构成比较级,比较级前可用much ,even , a little , a bit等词修饰,起强调作用.