Is it correct?
I read this sentence in a book "Repeating key words and using time-sequencing words is commonly done when describing a process." Is it correct to use "is" rather than "are"?

Question

Answer

Actually, it is perfectly correct. The topic here is ONE process, not a number of processes. Consider:

"(The process of) Repeating key words and using time-sequencing words is commonly done when describing a (different) process."

If the topic was referring to TWO processes, then the plural would be used. But then the sentence would change:
"BOTH repeating key words AND using time-sequencing words ARE commonly done when describing a process."

Answer

I agree with Randy.

Answer

No, it is incorrect. The plural should be used. “Repeating key words and using time-sequencing words” represents a compound subject consisting of two gerund phrases. (A gerund is the -ing form of a verb used as a noun.)

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