Sentence:  Mercer 's Whiteman association brought him into contact with Hoagy Carmichael , whose `` Snowball '' Mercer relyriced as `` Lazybones '' , in which form it <WSD>became</WSD> a hit and marked the real beginning of Mercer 's song writing career . 
Meaning of the word marked with <WSD> tags:  undergo a change or development