Table 2.

A set of 60 most common tri-grams

Tri-gram	Weighted frequency
Tested positive COVID	0.069332
Tested positive coronavirus	0.045802
President Donald Trump	0.044983
Personal protective equipment	0.039804
Confirmed case COVID	0.03488
New York city	0.03191
World Health Organization	0.028425
Center disease control	0.028324
Social distancing measure	0.026897
Due coronavirus pandemic	0.026391
Confirmed COVID case	0.024802
Coronavirus disease COVID	0.024442
Disease control prevention	0.023252
Health care worker	0.023102
Amid coronavirus pandemic	0.021448
People tested positive	0.021336
Due to COVID pandemic	0.020209
John Hopkins University	0.019181
Confirmed coronavirus case	0.019104
Number confirmed case	0.018606
Number COVID case	0.01772
Number coronavirus case	0.017468
Confirmed case coronavirus	0.017438
Tested positive virus	0.017265
Social distancing guideline	0.016958
Intensive-care unit	0.015946
Spread novel coronavirus	0.013718
County health department	0.013658
Practice social distancing	0.013599
Department public health	0.012858
Coronavirus task force	0.0126
Prevent spread COVID	0.012448
Public health official	0.011636
Bringing total number	0.011597
New coronavirus case	0.011139
Prevent spread coronavirus	0.010432
Novel coronavirus COVID	0.010243
Prime Minister Boris	0.009862
Protective equipment ppe	0.009651
Slow spread coronavirus	0.009387
Long-term care facility	0.008477
Social distancing rule	0.008442
Minister Boris Johnson	0.008237
New COVID case	0.007513
Prime Minister Narendra	0.007379
Total number case	0.007077
New case COVID	0.006727
Chief medical officer	0.006686
Amid COVID pandemic	0.004926
Minister Narendra Modi	0.004636
Slow spread COVID	0.004222
Due coronavirus outbreak	0.004134
Wearing face mask	0.004061
Health human service	0.00215
Health care system	0.002131
People stay home	0.001947
Positive case COVID or Positive COVID case	0.001921
Novel coronavirus pandemic	0.001721
Wear face mask	0.001662