tests by nicks0206 with the online test builder (197 tests)
Ranked by: number of candidates
1. Pretérito indefinido: irregular (346406 candidates)
2. Verbos con diptongación (176140 candidates)
3. Soler + infinitive (156616 candidates)
4. Gustar, doler, encantar ... (156017 candidates)
5. El pretérito perfecto compuesto (136257 candidates)
6. Comparison : tan..como, tanto ..como, tanto/a/os/as..como (102692 candidates)
7. Imperfect (102458 candidates)
8. Adjectives agreement (99669 candidates)
9. Gerund (91524 candidates)
10. Present (80368 candidates)
11. Present (63609 candidates)
12. Animals (60143 candidates)
13. Conditional - SI + sequence of tenses (59021 candidates)
14. Pretérito Indefinido. Verbs in -ZAR, -CAR, -GAR (57042 candidates)
15. Colours (53609 candidates)
16. Do some shopping (49845 candidates)
17. Pretérito indefinido (46357 candidates)
18. VERBOS DE CAMBIO (45432 candidates)
19. What the weather like? (44953 candidates)
20. Pero .?.../...sino...? (43071 candidates)