Here’s an example of indefinite pronouns as subjects in two clauses with singular verbs:
Nobody wants to help when something goes wrong.
Point 39 in the category of PRONOUNS/indefinite is defined as:
increasing range of indefinite pronouns (‘something’, ‘nobody’) as subjects, with a singular verb.
*Remember the inflectional -s at the end of a verb indicates that the verb is the third person singular. However, a much rarer structure using the third person imperative is possible:
Nobody say anything. (Grammarly is wrong!) 
An iWeb search for:
something|nobody _VVZ
1 NOBODY WANTS 19942
2 NOBODY KNOWS 18838
3 SOMETHING GOES 18724
4 SOMETHING HAPPENS 15446
That’s because if something happens just once or twice,
that’s really not enough to find any patterns.
5 NOBODY LIKES 8255
6 SOMETHING NEEDS 6347
7 NOBODY CARES 5885
8 SOMETHING TELLS 5387
9 NOBODY SEEMS 4570
10 SOMETHING COMES 3651
11 NOBODY GETS 2989
12 SOMETHING SEEMS 2961
13 SOMETHING WORKS 2529
14 SOMETHING CHANGES 2394
15 NOBODY NEEDS 1941
16 SOMETHING GETS 1896
17 SOMETHING BREAKS 1859
18 SOMETHING LOOKS 1651
19 NOBODY GIVES 1322
20 NOBODY THINKS 1270
21 SOMETHING MAKES 1205
22 NOBODY SAYS 1157
23 SOMETHING FEELS 1156
24 NOBODY BELIEVES 1155
25 NOBODY USES 1147
26 NOBODY UNDERSTANDS 1086
27 NOBODY EXPECTS 1031
28 NOBODY TALKS 1024
29 NOBODY GOES 1012
30 NOBODY MAKES 956
31 SOMETHING SOUNDS 914
32 NOBODY SEES 876
33 NOBODY TAKES 805
34 NOBODY COMES 766
35 SOMETHING MEANS 741
36 NOBODY NOTICES 736
37 NOBODY TELLS 711
38 SOMETHING BECOMES 685
39 NOBODY READS 660
40 NOBODY PAYS 634
41 NOBODY DESERVES 611
42 NOBODY WINS 599
43 SOMETHING APPEARS 595
44 NOBODY REMEMBERS 594
45 SOMETHING CATCHES 591
46 NOBODY LOVES 585
47 NOBODY BUYS 576
48 SOMETHING EXISTS 554
49 SOMETHING SMELLS 520
50 SOMETHING TAKES 503
51 SOMETHING FAILS 491
52 NOBODY LOOKS 456
53 SOMETHING OCCURS 439
54 NOBODY PUTS 435
55 NOBODY FEELS 428
56 SOMETHING STARTS 428
57 NOBODY ASKS 408
58 SOMETHING FALLS 404
59 NOBODY CALLS 392
60 NOBODY LIVES 389
61 SOMETHING MOVES 388
62 NOBODY BOTHERS 384
63 NOBODY ENJOYS 383
64 NOBODY LISTENS 377
65 SOMETHING POPS 370
66 NOBODY PLAYS 360
67 NOBODY DIES 346
68 NOBODY OWNS 329
69 SOMETHING COSTS 325
70 SOMETHING CAUSES 319
71 SOMETHING HITS 318
72 NOBODY SPEAKS 296
73 SOMETHING STOPS 295
74 NOBODY COMPLAINS 288
75 SOMETHING GIVES 288
76 SOMETHING TURNS 286
77 SOMETHING STICKS 280
78 SOMETHING TRIGGERS 270
79 SOMETHING HURTS 266
80 NOBODY WORKS 261
81 NOBODY DOUBTS 258
82 NOBODY ANSWERS 237
83 NOBODY BEATS 236
84 SOMETHING REQUIRES 230
85 SOMETHING KEEPS 217
86 NOBODY ELSES 213
87 NOBODY LEAVES 196
88 NOBODY DENIES 194
89 NOBODY MENTIONS 191
90 SOMETHING STINKS 190
91 NOBODY WRITES 189
92 NOBODY QUESTIONS 188
93 NOBODY DARES 187
94 SOMETHING SHOWS 187
95 NOBODY MINDS 186
96 SOMETHING BOTHERS 184
97 SOMETHING FANS 183
98 NOBODY FORCES 182
99 NOBODY HEARS 181
100 NOBODY OWES 180
A2:
becomes, believes, bothers, breaks, calls, cares, costs, fails, falls, fans, happens, hurts, keeps, means, minds, moves, nobody, notices, pops, sounds, turns, wins
B1:
appears, beats, complains, deserves, doubts, exists, expects, hits, mentions, owes, owns, requires, seems, smells, sticks
EXPERT EXAMPLE:
When people say they don’t know why something is right or wrong,
but they just know it’s right or wrong, they’re doing grammar right.