One big similarity between English and Greek/Romance languages is the use of auxiliary verbs (usually variation of "to be" or "to have") to specify tense. For example, "tha eiha kanei" (mod. Greek) and "j'aurais fait" (French) carry essentially the same meaning as "I would have done" in English. English does use more than the auxiliary verbs -- as in use of the words "would", "will", etc. -- but the similarity is there. I don't know if this was [Unknown site tag]'s original intent, but it was one thing that came to mind immediately.
Re: Speaking of nuances...