1. Problem in looking at grammar without a tagged corpus (e.g. passive, progressive)
   1. Google: give it to him / give him it
   2. Google: had been being watched/used
2. Difficulty of determining part of speech (POS): light, back, fine
3. Overall differences between nouns, verbs, adjectives, adverbs, and prepositions in four major registers (spoken, fiction, newspapers, and academic)
4. Nouns / pronouns
   1. relative frequency of nouns and pronouns
   2. pronouns -- personal
   3. pronouns -- relative
   4. N + N
5. Adjectives (taller v. more tall)
6. Verbs
   1. present v. past
   2. progressive (is Ving)
   3. passive (was Ved)
   4. modals
   5. stacking: was being Ved, has/had been Ved, has/had been being Ved
   6. phrasal verbs (turn down, burn up)
   7. constructions: seems to V / seems that ...
7. Contractions
8. Clefting (it 's [n*] that)

Charts from Biber (1998)