MOST是副词呀.你查一下字典就知道了.
most,mostly 和almost这三个词都可以作副词,但意义和用法不同.most用在形容词或副词前面,等于very,起加强语气的作用.表示“很、十分、非常”
most前面不可有定冠词the.如：
This is a most useful book． 这是一本很有用的书.
It's most dangerous to play with fire． 火是很危险的.
almost = very nearly.指在程度上相差很少,almost可与no,none,nothing,never,nobody等表示否定意义的词连用.如：
I almost missed the flight． 我差一点误了航班.
Almost no one believed what he said． 几乎没人相信他的话.
mostly＝mainly“大部分”“主要地”“通常地”.如：
The students in our class are mostly from the factory． 我们班的学生主要来自这家工厂.
His stories were mostly about his travels in foreign countries．
他的故事大多是关于他在国外旅游的经历.
所以你词性记错了.