I don't want to just pick on the immensely successful Dan Brown. It's a bit gauche. However, someone else did some criticism of some bad writing, which just happened to be in Dan Brown's new book, and it's an entertaining read. It's important to remember that all of us will write terrible sentences, and occasionally it's heartening to see that even those of us who sell many many many books are not immune.
And yes, they're not all single sentences, and no, I haven't confirmed these are really from the book...in truth, some of them are just too terrible to see print. Take for example the description of this watery cave:
Emerging from the darkness, a scene began to take shape … the interior of a cave … or a giant chamber of some sort. The floor of the cavern was water, like an underground lake.