From 11:00PM PDT on Friday, July 1 until 5:00AM PDT on Saturday, July 2, the Shmoop engineering elves will be making tweaks and improvements to the site. That means Shmoop will be unavailable for use during that time. Thanks for your patience!
In "Composed Upon Westminster Bridge," clothes are a metaphor for the way the city and nature in general seem to put on different appearances depending on the way the light "dresses" them. This raises the question of whether it's only the clothes that make the person beneath them beautiful, or whether that person is beautiful as well.
Line 4: The morning light is compared to clothes worn by London. A "garment" is just an article of clothing.
Line 5: The word "bare" could be a pun that means both "open to view" or "unadorned" but also "naked."