1) 大部分形容詞加-ly 可構成副詞。但 friendly，deadly，lovely，lonely，likely，lively，ugly，brotherly，仍為形容詞。

改錯：(錯) She sang lovely.

(錯) He spoke to me very friendly.

(對) Her singing was lovely.

(對) He spoke to me in a very friendly way.

2)有些以-ly 結尾既為形容詞，也為副詞。

daily，weekly，monthly，yearly，early

The Times is a daily paper.

The Times is published daily.