Q: What’s the general consensus on mixing tenses within the same sentence? Example: “I was delighted to see that your website was robust and user friendly.” Or: “I was delighted to see that your website is robust and user friendly.”
A: People routinely mix tenses in their sentences. The challenge is to make sure the sequence of tenses makes sense.
Both of the sentences you propose make sense, though their meanings may be slightly different. That’s because the simple past tense (“I was”) takes in a lot of territory—the very distant as well as the very recent past.
For example, these might be the expanded meanings of those sentences (the material in brackets is understood but not stated):
“[When I looked at it in 2009,] I was delighted to see that your website was robust and user friendly.”
“[When I looked at it this morning,] I was delighted to see that your website is robust and user friendly.”
In the first example, the observation took place quite a while ago, so the speaker doesn’t take for granted that the website is still the same.
In the second, the observation was very recent; speaker assumes the site still exists and is still robust and user-friendly.
When something has been done in the very recent past (like this morning), the speaker might even choose to use the present all around: “I am delighted to see that your website is robust and user friendly.”
These are subtle distinctions and not every usage authority would agree with us. But it’s a good idea to think of your readers. How would they interpret the mixing of tenses?
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