In 1 Cor 4:16 we have the Greek text:
παρακαλῶ οὖν ὑμᾶς, μιμηταί μου γίνεσθε
I would translate this as: "Therefore, I exhort you, become imitators of me."
The Jerome Latin text is:
Rogo ergo vos, imitatores mei estote (= I beg you to imitate my example)
The Clementine vulgate text says:
Rogo ergo vos, imitatores mei estote, sicut et ego Christi. (= I beg you to imitate my example as I am of Christ)
Note that the Clementine text has the extra phrase in bold above. I do not know how this has been added to the Greek text. However, just three MSS, 104 (1087 AD), 614 (13th cent), 629 (14th cent) also have this phrase added in the Greek. It appears that a scribe decided to add this phrase about the middle of the 11th century.