You say secondly when you want to make a second point or give a second reason for something.
例句
You need, firstly, a strong independent board of directors and secondly, an experienced and dedicated staff.你首先需要一個強大的獨立董事會，其次需要一批富有經(jīng)驗并且愛崗敬業(yè)的員工。
英漢詞典釋義
adv.
第二,其次
To start with,we haven’t enough money,and secondly we haven’t enough time.首先,我們沒有足夠的資金;其次,我們沒有足夠的時間。We can’t give Smith the position. To begin with,he’s too young;secondly,I want my son to have the job.我們不能把這一職位給史密斯。第一,他太年輕;第二,我想讓我兒子就任這一職位。