tests by felin with the online test builder (215 tests)
Ranked by: number of candidates
1. Much, many, little and few (376588 candidates)
2. Future continuous and future perfect. (238286 candidates)
3. I wish, if only (234659 candidates)
4. Adjectives - ing and ed (230415 candidates)
5. Adjectives and adverbs (194557 candidates)
6. Prefixes (1) (191766 candidates)
7. Although / in spite of / despite (175982 candidates)
8. Adverbs : Still, yet and already (167401 candidates)
9. Can, could and be able to. (112180 candidates)
10. Both / both of / neither / neither of / either / either (103277 candidates)
11. Is or are? (75565 candidates)
12. A, an, the, no article (74934 candidates)
13. Little, a little, few and a few. (74474 candidates)
14. As/Like (72330 candidates)
15. Modal verbs (71159 candidates)
16. Another, other or others (68459 candidates)
17. Demonstrative adjectives and pronouns (66341 candidates)
18. At the bank (66173 candidates)
19. Present perfect : continuous or simple (61054 candidates)
20. All / all of most / most of no / none of etc. (1) (58988 candidates)