I merely speak English and have been learning Spanish. (Enough so that using capital letters for languages seems soo weird to me now!) In doing so, I've learned at least as much about English and Latin. I wish I'd set out to learn the other Romance languages at the same time[0], as learning one sheds so much light on the others. e.g. in French, most words are recognizable as either similar to their English or Spanish/Latin equivalents. And the verb structure (the hardest thing about learning Spanish, although it almost seems natural to me now) is very similar in all Romance languages. ('Je sais' may look very different to 'yo sé', but (in some spanish-speaking regions at least) they're pronounced almost identically. In spanish you usually don't say 'yo' because the verb endings tells you who, but in French enough of the different endings have become the same that you do always have to say who.) Romanian looks crazy with all the words ending in -u, but all those words ending in -o in spanish came from Latin nouns ending in -um; the -m was gradually dropped, and -u became -o. (I can kind of read Portuguese - it's like Spanish with extremely bad spelling - or vice versa.) I made a page a few years ago comparing common words, verbs etc in those languages http://www.adamponting.com/romance-languages/

[0] Well, maybe not - getting on top of one Romance verb system was enough, it seemed soooo weird and complicated in the beginning. Although I'm still a novice at using the subjunctive.