YOU SAID:
He everyone. Welcome back to my lab.
INTO JAPANESE
彼はみんな。私の研究室へようこそ。
BACK INTO ENGLISH
He is everyone. Welcome to my laboratory.
INTO JAPANESE
彼はみんなです。私の研究室へようこそ。
BACK INTO ENGLISH
He is everyone. Welcome to my laboratory.
You've done this before, haven't you.