1. Active voice versus passive voice
2. Ambiguities
3. Apostrophes
4. Auxiliary verbs
5. Brevity
6. British versus American English
7. “Can” versus “may”
8. Capitalization
9. Cognates and false cognates
10. Colloquialisms
11. Commas versus periods
12. Compound subject + verb
13. Concise writing
14. Conditional verbs
15. Direct versus indirect object
16. “Either” versus “neither”
17. Figures of speech
18. Foreign words and expressions
19. Gender pronouns
20. Gerund versus infinitive
21. Homonyms and synonyms
22. Indefinite pronouns
23. Introductory phrases
24. Metaphors
25. Misuse of common expressions
26. Modal auxiliaries
27. Modifiers
28. Nouns used as verbs
29. Numerals versus words for dates
30. Paragraphing
31. Parallel construction
32. Parentheses and parenthetical expressions
33. Period versus comma
34. Personal pronouns
35. Prepositions
36. Quotation marks
37. Redundancies
38. Run-on sentences
39. Sentence fragment
40. “Shall” versus “will”
41. “Should” versus “must”
42. Singular versus plural form of words
43. Split infinitives
44. Subject/verb agreement
45. “That” versus “which”
46. Temporal and causal use of “since”
47. Use of the possessive
48. Verb tenses
49. “Who” versus “whom”
50. Word order