Between 'whenever' and 'as'

[Miss Mae]

If I use 'whenever' in the sentence, But through the Nile, cities and civilizations sprang whenever the river overflows and scatter fertile soil onto its banks, wouldn't it seem that cities and civilizations still arise in Egypt today since the river still run off every high tide?

[Joe Carillo]

Yes, that sentence would seem to mean that cities and civilizations still arise in Egypt today every time the river run offs at high tide—a state of affairs that couldn’t be possibly true. The semantic problem in that sentence is due to the wrong use of the temporal subordinating conjunction “whenever” as well as the wrong use of the simple past-tense “sprang” in the main clause and of the present-tense “overflows and scatters” in the subordinate clause.

For that complex sentence to yield the correct sense, the sequence of tenses in the two clauses should be corrected as follows:

“But through the Nile, cities and civilizations had sprung in places where the river would overflow and scatter fertile soil onto its banks.”

“Had sprung” is, of course, used here to indicate certain events in the indefinite past, and “would overflow and scatter” is used to indicate that the two indicated actions repeatedly (seasonally) happened in the past.

[Miss Mae]

Uh, oh. I forgot about this question. Probably because I had reconstructed the paragraph it was written on. But from your pointers, did I finally get this sentence correct?

The soil from its depth had scattered whenever the river would overflow.

[Joe Carillo]

No, I'm afraid the sequence of tenses in that sentence of yours is incorrect. It should be:

"The soil from its depth would scatter whenever the river overflowed."

The verb in the main clause is in the modal "would scatter" to indicate regular recurrence of the resulting action, while the verb in the adverbial clause is in the simple past tense.

[Miss Mae]

But Sir, don't you think that would bring me back to my first problem? That sentence is part of the paragraph wherein I illustrated how the cities and civilizations in Egypt came about. If I say The soil from its depth would scatter whenever the river overflowed, wouldn't it seem that that scene is still happening even today?

[Joe Carillo]

If you want to evoke the sense that the situation still applies today, the sequence of tenses in the sentence should be as follows:

"The soil from its depth scatters whenever the river overflows." (simple present tense - simple present tense)

For the historical past with that situation no longer subsisting, this sequence of tenses applies:

"The soil from its depth would scatter whenever the river overflowed." (past modal - simple past tense)

[Miss Mae]

Thank you.