dangling modifier

A dangling modifier is a descriptive phrase or clause whose intended target never appears in the sentence, so it fastens onto whatever subject is there. Walking into the room, the temperature was low is the standard shape: the one walking should be a person, but the sentence's subject is the temperature, so the temperature is left walking. The repair is to supply the missing subject and, if necessary, make it the subject of the main clause: walking into the room, the nurse noticed the room was cold. The two symptoms to look for are a sentence that begins with a verb form in -ing or a past participle followed by a comma, and a main clause whose subject cannot logically perform that action. Dangling and misplaced are cousins — the misplaced one has an intended word it simply sits next to wrongly, while the dangling one has no word at all — and both are answered by asking who is doing this?