Perhaps I’m just overly sensitive, but this always grates a bit on my ears. My guess is that it’s the result of the popularity of “tweeting,” where one is quite limited by the number of characters that can be used to send a message. Still, I’m old fashioned enough that it bothers me.
I was taught that an adverb (defined by Dictionary.reference.com as “A part of speech that modifies a verb, an adjective, or another adverb. Adverbs usually answer such questions as ‘How?’ ‘Where?’ ‘When?’ or ‘To what degree?’ The following italicized words are adverbs: ‘He ran well’; ‘She ran very well’; ‘The mayor is highly capable.”) is perfectly proper and, in fact, made things clearer by indicating the modification intended. The same source goes on: “Note: Adverbs are often formed by adding -ly to an adjective, as in truly or deeply.”
There are, of course, ways to phrase this sort of idea which avoid the need for the “ly” ending, but they are often somewhat awkward sounding and, as indicated, the “ly” ending isn’t always required for the adverbial form, but it often makes a lot of sense to use it, at least to my old-fashioned ears.
I suppose that some of my prejudice for the use of the “ly” suffix may come from listening to the “LY” song on The Electric Company when my girls were small. This little song, composed and performed by Tom Lehrer, stuck in my head, and, while I didn’t remember it in great detail until I looked it up, I did remember its existence, probably because I was amused by the fact that Lehrer wrote and sang it. Now, I was first exposed to his songs when I was in high school and felt they were among the funniest (and frequently the most risqué) that I had ever heard at the time. I think they still are. (Some of my more recent students may remember my fondness for playing his Oedipus Rex at the beginning of Lit/Crit class discussions of that play.)
I suppose that I found his songs fascinating because, while he frequently walked the edge of being filthy, he never (to my knowledge) actually used “bad” words. That is, he used innuendo to make the listener understand what he was talking about (especially when touching on sexually related topics) but he rarely, if ever, used “impolite” language. I often wish that more modern comic authors would follow his lead and use carefully chosen, witty language, rather than relying of the shock value of “dirty” words as the source of humor.
In any case, I found the idea of this author/composer writing for The Electric Company, a television program created by CTW (the Sesame Street people) for kids who had outgrown the preschool show, so ironic, that it stuck with me. I’m digressing, I know, by I’d encourage looking up his “LY” song at: https://www.youtube.com/watch?v=0ImDSrQ3tY8&index=38&list=PL1954DB8E36117DA6
and, you can probably find recordings of many of his other pieces on line. I know you can still find them in the “comedy” section in various stores which sell CDs.
Okay, I’ve gone off track a bit (one of the privileges of being in control) but as I’ve touched on before (and probably will again) I think that language is important. I expect its usage to grow and change over time, but the lack of willingness to use it carefully suggests a sort of sloppiness which I find too bad, especially from those (teachers, broadcasters, authors, etc.) who probably should be role models for the best use of the language. Certainly, the simple use of the “ly” ending can be useful, make the words flow more easily and make the meaning of what you are trying to say clearer. I encourage its use, quite strongly.
Note: Twenty examples of the use of the “ly” ending to indicate an adverb, only three of them in the quote (and I wasn’t even trying).