friendly最高级是most 还是去y加est

两个都可以的,口语中都用得到,而且老师也是这样教的
“in formal English the comparative degree is " more friendly" (Pat is more friendly than her sister). In informal English "friendlier than" is pretty much used (Pat is friendlier than her sister).
The superlative degree is "the most friendly of" (Pat is the most friendly of all my cousins / [...[ the friendliest of them all).”

[ 比较级friendlier 最高级friendliest ] 例句 Nowhere in the world have 而一个空就是去y改i加er或est了

比较级：more friendly
最高级：friendliest 是改y为i加，我们老师讲的、

the most friendly

比较级friendlier 最高级friendliest

most friendly