Hi, Mike Powell!
I read your message from 04.05.2019 03:05

 ak>> If we apply Mike's rule we'll see that "progress" is an
 ak>> uncountable noun, as should be "lack", and,
therefore, it should
 ak>> be "lack of progress MEAN they are not..." So the rule is not
 ak>> working.

 MP> No, it would be lack and means. I may be using "singular"
 MP> and "uncountable" interchangably (and incorrectly!), but I would
 MP> use MEANS in your example also.

I understood where I had misunderstood. I thought that I should use the
verb form like "meanS" only with countable nouns. For instance, I
thought that

Water erode rock.

but in reality

"Water erodes rock."

;-) Well, poor practice.

Bye, Mike!
Alexander Koryagin
english_tutor 2019

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