Modality expresses something about the attitude of the ‘speaker’. Here are some modal adverbs that students can use.
B1 Modal Adverbs:
definitely, fortunately, indeed, likely, obviously, totally
B2 Modal Adverbs:
apparently, essentially, evidently, literally, necessarily, positively, presumably, strictly, surely, truly, undoubtedly
C1 Modal Adverbs:
all things considered, inevitably, noticeably, seemingly, technically, unnecessarily, unquestionably
C2 Modal adverbs:
allegedly, reportedly, scarcely, unavoidably, undeniably
In the English Grammar Profile, point 229 in the category of MODALITY at C2, is simply defined:
‘must’ with a wide range of adverbs.
The problem with this explanation is that it doesn’t say whether range must include ‘modal adverbs’ not just a wide range of adverbs with the modal auxiliary ‘must’.
This we can try to guess from the examples given:
 “certainly” which is A2 in the EVP,
 “clearly” A2 or B1 depending on the sense and
 “completely” which is B1.
Here’s a long list of modal adverbs and modal adverb phrases. Black means they are unlisted in the English Vocabulary Profile.
Otherwise, we might assume safely that any B1 adverbs and higher found in the mid position would constitute a wide range…
A search in iWeb for:
must_VM definitelyfortunatelyindeedlikelyobviouslytotally _V
1 MUST INDEED BE 292
2 MUST OBVIOUSLY BE 263
3 MUST DEFINITELY BE 151
4 MUST INDEED HAVE 110
5 MUST OBVIOUSLY HAVE 52
6 MUST DEFINITELY TRY 29
7 MUST DEFINITELY HAVE 26
8 MUST INDEED COME 16
9 MUST TOTALLY REJECT 13
10 MUST INDEED TAKE 12
11 MUST INDEED GO 12
12 MUST DEFINITELY VISIT 11
must_VM apparentlyessentiallyevidentlyliterallynecessarily
positivelypresumablystrictlysurelytrulyundoubtedly _V
1 MUST SURELY BE 2483
2 MUST NECESSARILY BE 1800
3 MUST SURELY HAVE 837
4 MUST NECESSARILY HAVE 311
5 MUST TRULY BE 245
6 MUST SURELY KNOW 105
7 MUST STRICTLY ADHERE 97
8 MUST NECESSARILY FOLLOW 87
9 MUST SURELY RANK 83
10 MUST SURELY COME 72
11 MUST STRICTLY FOLLOW 68
12 MUST SURELY GO 62
13 MUST STRICTLY COMPLY 61
14 MUST UNDOUBTEDLY BE 60
15 MUST NECESSARILY INCLUDE 55
16 MUST NECESSARILY EXIST 50
17 MUST NECESSARILY TAKE 49
18 MUST EVIDENTLY BE 47
19 MUST NECESSARILY INVOLVE 44
20 MUST SURELY SEE 42
21 MUST TRULY BELIEVE 42
22 MUST TRULY UNDERSTAND 40
23 MUST NECESSARILY LEAD 39
24 MUST SURELY MAKE 37
25 MUST NECESSARILY REMAIN 37
26 MUST LITERALLY BE 37
27 MUST ESSENTIALLY BE 37
28 MUST NECESSARILY FAIL 36
29 MUST NECESSARILY COME 36
30 MUST TRULY HAVE 35
I will not even start on whether or not the verbs that are found with lowerlevel adverbs should also constitute range points. Also, note that “completely” is a very rare adverb to find naturally in this construction which begs the question of whether following given examples would constitute for good choices of what to teach students. Therefore, let’s look for some proof outside of the English Grammar Profile! Take a look at what occurs most frequently online in the iWeb corpus for must _rr _v?i*
:
On the right are adverbs that are A2 or lower. On the left are adverbs that are B1 or higher. There are no C2 adverbs in these top 100 Ngrams.
1 MUST ALSO BE 43818 (B1)
2 MUST ALWAYS BE 14838
3 MUST ALSO HAVE 9845
4 MUST STILL BE 6368
5 MUST NEVER BE 4123
6 MUST THEREFORE BE 4103
further collocations:
1 CONSIDERED (VVN ) 104
2 TAKEN (VVN ) 96
3 CAREFUL (JJ ) 42
4 UNDERSTOOD (VVN ) 37
5 REGARDED (VVN ) 35
*There were only two examples in Open Cambridge Learner Corpus (Uncoded) and they both were @ C1 in :
 I must therefore advise you to correct your original advertisement and to make a more reliable one without further delay.
 In addition, some new employees have not [got] a personal computer and must therefore use other personal computers or wait until some are free.
7 MUST SUCCESSFULLY COMPLETE 3550
further collocates 4 left and right:
1 STUDENTS (NN2 ) 973
2 STUDENT (NN1 ) 314
3 COURSE (NN1 ) 234
4 COURSES (NN2 ) 217
5 PROGRAM (NN1 ) 179
6 CANDIDATES (NN2 ) 153
7 TRAINING (NN1 ) 147
8 LEAST (RR22 ) 141
9 MINIMUM (NN1 ) 137
10 APPLICANTS (NN2 ) 135
*none found in OCLCU
8 MUST ALSO PROVIDE 3132
9 MUST ALSO COMPLETE 2943
10 MUST EITHER BE 2933
(This could be considered a conjunction)
further collocates 4 to the left and right of “must either be”:
1 APPLICANTS (NN2 ) 62
2 CITIZEN (NN1 ) 49
3 RETURNED (VVN ) 26
4 APPLICANT (NN1 ) 24
5 ELIGIBLE (JJ ) 24
*2 examples in OCLCU.

C1 student: They must either return to society or leave it definitively, and either course means the end of the literature they guard.

C2: To do that he must either be a robot or a phenomenon.
11 MUST ALSO INCLUDE 2742
12 MUST SURELY BE 2486 (modal adverb)
1 AWARE (JJ ) 19
2 ULTIMATE (JJ ) 13
3 CONTENDER (NN1 ) 10
4 WORST (JJT ) 10
5 REGARDED (VVN ) 9
*one example at C2:
Thus, it is only a widespread moralistic assumption of the culture I am part of (a mixture of catholic distrust of economic profit and love for the poor, regardless of their usual quality, and the vulgarized marxist idea according to which if one gets richer, the amount of wealth he has come into possession with must surely have been the outcome of somebody else’s deprivation) that if there were fewer rich people poverty rates would be lower.
13 MUST ALSO TAKE 2483
14 MUST ALSO CONSIDER 2314
15 MUST ALSO SUBMIT 2281
16 MUST ALSO MEET 2040
17 MUST NECESSARILY BE 1798
1 TRUE (JJ ) 23
2 SUBJECT (II21 ) 19
3 CONSTITUTION (NN1 ) 15
4 PROPORTION (II32 ) 14
5 CARRIED (VVN ) 13

C2: For this reason Henry VIII needs desperately the balance provided by Thomas More, and for this same reason the two opposed attitudes must necessarily and inevitably collide.

C1: The reason is quite simple: those who manage to influence people so that they are empowered to engage in creative work must necessarily belong to a separate sort of mankind.
18 MUST ALSO PAY 1764
19 MUST ALREADY BE 1652
20 MUST ALSO ENSURE 1575
21 MUST ALSO MAKE 1508
22 MUST NEVER FORGET 1502
23 MUST ALWAYS HAVE 1429
24 MUST ALREADY HAVE 1359
25 MUST ALSO PASS 1047
26 MUST ALWAYS REMEMBER 1034
27 MUST REALLY BE 997
28 MUST JUST BE 990
29 MUST ALSO REMEMBER 976
30 MUST ALSO COMPLY 918
31 MUST BOTH BE 904
32 MUST ALSO KEEP 901
33 MUST ALSO KNOW 863
34 MUST ALSO SHOW 850
35 MUST SURELY HAVE 839
36 MUST ALSO UNDERSTAND 833
37 MUST ALSO GIVE 791
38 MUST ALSO DEMONSTRATE 785
39 MUST EITHER HAVE 766
40 MUST ALSO USE 762
41 MUST ALWAYS KEEP 704
42 MUST SUCCESSFULLY PASS 668
43 MUST OFTEN BE 640
44 MUST STILL HAVE 640
45 MUST CONSTANTLY BE 636
*none
46 MUST CERTAINLY BE 627 (our EGP given)
C2: There must certainly be other solutions to the problem of need for space for new houses.
47 MUST ALSO LEARN 613
48 MUST CURRENTLY BE 593
*none
49 MUST ALSO GO 587
50 MUST ALSO SIGN 578
51 MUST ALSO CONTAIN 568
52 MUST ALSO LOOK 562
53 MUST ALSO FILE 560
54 MUST IMMEDIATELY NOTIFY 560
55 MUST ALSO MAINTAIN 555
56 MUST CLEARLY STATE 546 (our EGP given)
*none
57 MUST ALSO WORK 545
58 MUST ALSO APPLY 539
59 MUST ALSO SPECIFY 539
60 MUST ALSO OBTAIN 535
61 MUST SATISFACTORILY COMPLETE 532
1 STUDENTS 185
2 POINTS 74
3 STUDENT 68
4 GRADUATE 66
5 COURSE 43
6 REQUIREMENTS 36
7 COURSES 34
8 MINIMUM 28
9 PROGRAM 27
10 RESIDENT 26
*none
62 MUST ALSO ADD 528
63 MUST EXACTLY MATCH 525
64 MUST ALREADY EXIST 519
65 MUST ALSO POSSESS 519
66 MUST ALSO SAY 516
67 MUST ACTUALLY BE 513
68 MUST ALWAYS REMAIN 513
69 MUST THEREFORE HAVE 504
70 MUST GENERALLY BE 502
further collocates:
1 WITHIN (II ) 40
2 MADE (VVN ) 30
3 ABLE (JK ) 21
4 PAID (VVN ) 17
5 HOST (NN1 ) 14
*none
71 MUST ALSO HOLD 501
72 MUST ALSO REGISTER 498
73 MUST ALSO DO 495
74 MUST ONLY USE 492
75 MUST SOMEHOW BE 476
1 RELATED (VVN ) 23
2 LINKED (VVN ) 10
3 CONNECTED (VVN ) 8
4 CAPABLE (JJ ) 7
5 PUNISHED (VVN ) 6
*none
76 MUST USUALLY BE 475
77 MUST ALSO FOLLOW 474
78 MUST ULTIMATELY BE 461
1 JUDGED 12
2 APPROVED 11
3 BASED 11
4 GOD 10
5 SATISFIED 9
*none
79 MUST CAREFULLY CONSIDER 455
80 MUST ALSO NOTIFY 448
81 MUST EVER BE 447
82 MUST ALSO RECOGNIZE 442
83 MUST ALWAYS USE 424
84 MUST ALSO AGREE 414
85 MUST CORRECTLY ANSWER 394
*none
86 MUST ALSO ADDRESS 393
87 MUST ALSO SET 388
88 MUST ALSO BRING 381
89 MUST ALSO ACCEPT 380
90 MUST ALSO STATE 380
91 MUST STILL MEET 372
92 MUST ALSO FIND 371
93 MUST ALSO GET 369
94 MUST ALSO REPORT 369
95 MUST STILL PAY 369
96 MUST ALSO CHANGE 355
97 MUST ALSO SATISFY 355
98 MUST NEVER HAVE 347
99 MUST SIMPLY BE 347
*none
100 MUST ALSO SEND 346
B1 (adverbs by EVP in the above strings):
correctly, either, generally, somehow, therefore
B2
constantly, currently, necessarily, simply, successfully, surely
C1
satisfactorily, ultimately
Note how rare “completely” is actually found online.
1 MUST COMPLETELY FILL 66
2 MUST COMPLETELY COVER 48
3 MUST COMPLETELY REMOVE 40
4 MUST COMPLETELY UNDERSTAND 39
5 MUST COMPLETELY AVOID 16
What adverbs do our learners use at lower levels then?
For starters, there were zero examples in B1 in the Open Cambridge Learner Corpus (Uncoded)! It seems then that the data set is different to that which the English Grammar Profile uses since there is an adverb range point for B1. Here are all the examples in the OCLCU for B2 (uncoded) put through antconc: