Another site:
AllTop 200 most popular tests to learn English...
1) Test de niveau anglais (webmaster) 6 778 723
2) Placement test : grammar for beginners (anonyme) 5 992 796
3) A/AN (webmaster) 5 365 548
4) Auxiliary BE (webmaster) 3 224 456
5) Present continuous (webmaster) 2 999 416
6) Present simple (webmaster) 2 915 475
7) Present simple (webmaster) 2 597 761
8) Present continuous (webmaster) 2 435 121
9) Adjectives (webmaster) 2 093 712
10) A/an (anonyme) 2 015 542
11) Present perfect simple (webmaster) 1 644 035
12) Preterite (webmaster) 1 628 946
13) Vocabulary - Placement test (bridg) 1 619 320
14) Preterite (webmaster) 1 448 038
15) Short placement test (webmaster) 1 443 663
16) To be (bridg) 1 406 382
17) What time is it? (webmaster) 1 349 523
18) Present perfect (webmaster) 1 346 575
19) The alphabet in English (webmaster) 1 321 216
20) Adjectives (anonyme) 1 216 059
21) What time is it? (webmaster) 1 208 741
22) Numbers (webmaster) 1 188 631
23) 'A' ou 'An' (anonyme) 1 175 698
24) Two presents: present continuous, present simple (webmaster) 1 149 567
25) To be (bridg) 1 145 656
26) Comparatives / Superlatives (webmaster) 1 104 757
27) Numbers (webmaster) 1 070 938
28) CAN / MUST (webmaster) 1 058 767
29) THE/ A / AN / nothing (webmaster) 1 033 899
30) Comparatives (webmaster) 1 007 301
31) Family life (bridg) 1 000 927
32) Numbers > 100 (webmaster) 986 411
33) Future (going to/will/present continuous) (anonyme) 964 232
34) Plural (webmaster) 955 849
35) Superlatives (webmaster) 875 363
36) Adjectives (anonyme) 874 904
37) Simple present (bridg) 854 083
38) Spelled words N°1 (bridg) 850 253
39) Placement test beginners: Check your spelling (anonyme) 830 134
40) Introducing oneself (webmaster) 827 245
41) Adverbs of frequency (anonyme) 817 642
42) Family (bridg) 784 869
43) General test-End of high school / Beginning of university (webmaster) 782 944
44) Present simple (anonyme) 781 019
45) Frequency adverbs (webmaster) 777 842
46) Present BE + Ving (bridg) 765 206
47) Genitive (webmaster) 723 735
48) Passive form (anonyme) 722 887
49) Family tree (anonyme) 719 479
50) Preterite: simple or continuous? (webmaster) 716 854
51) Placement test (beginners) (lili73) 701 215
52) Past simple or present perfect (anonyme) 694 372
53) Future (webmaster) 676 017
54) 2 Preterites (webmaster) 662 167
55) Present perfect simple (bridg) 661 509
56) Preterite (webmaster) 620 583
57) List of 200 irregular verbs and audio (bridg) 616 147
58) Modals (webmaster) 612 765
59) Spelled words N°2 (bridg) 609 259
60) Height (webmaster) 606 361
61) Modals (webmaster) 605 675
62) Articles a / an / the (anonyme) 596 760
63) Plural forms (bridg) 577 564
64) Nationalities (webmaster) 574 333
65) Past continuous / Past simple (anonyme) 566 662
66) Irregular plurals (bridg) 553 707
67) Two presents: simple and continuous (webmaster) 549 731
68) Preterite (bridg) 549 151
69) Superlatives (frapedur) 539 140
70) Vocabulary: greeting people (here4u) 536 474
71) Give your opinion (bridg) 532 052
72) Adverbs of Frequency (bridg) 517 007
73) Present simple or continuous (anonyme) 511 452
74) Present perfect / preterite ? (anonyme) 509 839
75) Possessive case (anonyme) 480 732
76) Countries & nationalities (bridg) 473 566
77) 'The' or nothing? (webmaster) 471 279
78) Past tenses (bridg) 470 962
79) Introducing oneself (easy) (webmaster) 470 759
80) Passive voice (webmaster) 463 573
81) Present Simple vs. Past Simple (anonyme) 457 419
82) Questions : how to ask them (anonyme) 448 502
83) General Test II / End of high school / Beginning of universi (webmaster) 446 200
84) IN, ON, AT or TO? (webmaster) 445 343
85) Relative pronouns (webmaster) 444 611
86) Comparative of superiority (anonyme) 438 794
87) How to pronounce the final -ED? (past simple) (webmaster) 437 980
88) Relative clauses (webmaster) 423 367
89) Sounds: [h] (webmaster) 419 554
90) Comparative (anonyme) 413 769
91) A/an/Ø (bridg) 398 878
92) Past simple (anonyme) 397 525
93) Future simple (anonyme) 396 466
94) This / That / These / Those (webmaster) 392 577
95) Conditional (webmaster) 391 727
96) Passive voice (anonyme) 390 728
97) Comparing (webmaster) 388 060
98) Can / could/ may/ might (woodyrun) 379 544
99) Present perfect or past tense (anonyme) 377 567
100) Much, many, little and few (felin) 372 913
101) Personal pronouns (anonyme) 371 344
102) Preterite continuous (BE + -ING) (webmaster) 369 393
103) Some, any, no, enough, too/too much/too many (webmaster) 368 138
104) Genitive case (bridg) 368 113
105) Confusing words - Placement test (bridg) 364 542
106) Irregular verbs (webmaster) 363 644
107) Numbers from 1 to 10 (anonyme) 361 557
108) Past perfect simple, past perfect continuous (anonyme) 360 933
109) Present continuous or present simple (webmaster) 359 607
110) Present perfect or preterite? (anonyme) 356 998
111) Simple Past : regular verbs (anonyme) 353 177
112) Comparative Adjectives (bridg) 352 266
113) Who, Whom, Which, or Whose? (anonyme) 348 850
114) Past simple (video) (anonyme) 348 503
115) Past simple or past continuous (anonyme) 342 923
116) While / When (anonyme) 338 885
117) What time is it? (webmaster) 337 989
118) Modals (tinou) 336 593
119) Modal: may/might (anonyme) 334 231
120) Cardinal and ordinal numbers (anonyme) 328 761
121) The superlative (anonyme) 325 647
122) Possessive adjectives and pronouns (woodyrun) 324 240
123) How to talk about the weather (lili73) 320 890
124) Since and for (anonyme) 318 897
125) Flags (webmaster) 317 616
126) Irregular verbs (bridg) 316 054
127) Prepositions - in, on, at (anonyme) 314 146
128) Pronouns (woodyrun) 313 737
129) Tenses (anonyme) 311 988
130) Placement test 3 (webmaster) 310 494
131) Order of adjectives (webmaster) 306 604
132) Could/Couldn't (laure95) 305 892
133) Comparative (anonyme) 304 672
134) Agreement Tags (webmaster) 304 065
135) Adjectives and prepositions (anonyme) 304 057
136) Asking questions (webmaster) 303 110
137) Present perfect OR simple past? (bridg) 298 393
138) Questions in the past tense (anonyme) 297 590
139) Superlative Adjectives (bridg) 295 845
140) Uncountable nouns (webmaster) 295 679
141) Object pronouns (bridg) 295 031
142) Placement test 1 (anonyme) 292 815
143) Passive form (anonyme) 291 425
144) Present simple (anonyme) 291 340
145) Prefer/rather (bridg) 289 431
146) Can/Must/Should (laure95) 289 431
147) Past perfect (lili73) 288 326
148) Must or Have to? (woodyrun) 287 570
149) The/an/nothing (bridg) 285 292
150) To be (anonyme) 283 496
151) Can and can't (laure95) 281 656
152) Vocabulary: asking and answering (here4u) 280 444
153) Modal verbs (bridg) 277 302
154) Some / Any / no... (bridg) 270 535
155) Days of the week (bridg) 269 110
156) So / neither (anonyme) 264 367
157) Past simple (video) (anonyme) 263 740
158) Used to (bridg) 260 371
159) Present continuous (chnawa) 260 252
160) Should / must (anonyme) 259 651
161) Past tense (anonyme) 259 334
162) Vocabulary: on the phone (here4u) 258 735
163) Find out a quantity (webmaster) 258 568
164) Superlative + and adjective (anonyme) 257 228
165) Articles : a / an / the / Ø (anonyme) 257 044
166) Comparative and superlative (anonyme) 255 352
167) Numbers 1/100 (anonyme) 253 658
168) Modal can (video) (anonyme) 253 008
169) Comparatives (anonyme) 248 414
170) Relatives pronouns (who, which, that...) (anonyme) 247 846
171) Vocabulary: at the restaurant (here4u) 245 657
172) A few, a little, few, little (anonyme) 245 373
173) Would rather / would prefer to (anonyme) 244 266
174) Present continuous and the Going to form (anonyme) 242 628
175) Should/ have to/ must (anonyme) 240 000
176) Have something done (anonyme) 239 840
177) The past (webmaster) 237 806
178) Used to/would (woodyrun) 237 659
179) Future continuous and future perfect. (felin) 237 615
180) How to ask a question in English (bridg) 235 445
181) I wish, if only (felin) 234 086
182) Pluperfect (webmaster) 233 950
183) Countable or Uncountable? (webmaster) 233 153
184) Some / any (younes91) 232 863
185) Should / shouldn't (anonyme) 231 534
186) Present simple or continuous (bridg) 230 799
187) Adjectives - ing and ed (felin) 229 085
188) Hypothesis (webmaster) 228 132
189) Auxiliary BE (anonyme) 226 445
190) Articles a/an/the/0 (bridg) 226 286
191) Article The or nothing (anonyme) 225 945
192) Must or mustn't (laure95) 225 642
193) Present perfect with Ever - never - (anonyme) 225 523
194) Present continuous OR Present simple? (bridg) 225 436
195) Simple Preterite OR Preterite (BE+ing) (webmaster) 222 826
196) To / in order to / so as to / so that (irish21) 220 204
197) Present perfect (bridg) 219 500
198) Comparison (komiks) 218 819
199) What time is it ? (anonyme) 217 645
200) Indirect speech (bridg) 216 635
