Writing questions

(According to the recipe, Franciso was (suppose to use) buttermilk, but since he (had none), he (substituted) regular milks soured with lemon juice.
Why is the answer b
(Even) after (lowering) the volume, Suzanne found that her electric guitar (so annoyed) her neighbors that (they) complained to the building’s manager.
I thought the answer was c because it sounded weird, but apparently there is no error

  1. The correct form is "supposed to", with the "d." Get used to that. Your freshman composition instructors will nail you for it every time. Writers often neglect it because, when most people speak, the "d" and the "t" in "to" combine to make a single sound.
  2. "X so annoyed Y that" is an old-fashioned construction, but you'll see it in older books, and some writers continue to use it. It is the equivalent of writing, "X annoyed Y so much that" (Obviously, other words can be used besides "annoy")