I’ve been thinking about this “saving time” conundrum for two days now. I know instinctively that “I save my time by using a computer” sounds wrong. But I’ve had a hard time trying to figure out exactly why.
Just now I had an insight. Forget about “time” for a bit. The word “save” is the key here. Let me give you an example. A preacher might get up in the morning and turn his eyes toward heaven and say “Lord, I will save you souls today.” (“You” is the indirect object of “save.”) Later in that day the preacher confronts a group of sinners and proclaims to them “Brothers and sisters, I will save your souls today.” See how the first sentence uses “you” and the second sentence uses “your.”
Let’s say a gardener sees your roses are turning brown. He will tell you “I will save your roses.” But if you call a florist and tell him you want to order some flowers for later, he will say “OK, I will save you roses.”
What’s the difference between the sentences? The Lord does not yet own the sinners’ souls. But the sinners do. The preacher is doing the saving for the benefit of the Lord. You do own the roses in the garden, but you haven’t paid for the ones in the florist shop yet. The florist is holding the roses for your benefit.
I want to avoid using the word “her” because “her” is both the objective case of “she” and the adjectival form of “she.” I found her because her dog barked.
So let’s look at the sentence “I save my time by using a computer.” If it were unclear for whom was being saved, the sentence might be reformulated to say:
“I save myself time by using a computer.” (“I save me time” is just wrong, but that’s another discussion.)
“I save him time by using a computer.”
“I save my boss time by using a computer.”
If it is abundantly clear whose time is being referred to, you can just drop the indirect object and say “I save time by using a computer.”
Time is a more abstract quantity than roses are. You can see whose hand the roses are in, but not so much with time. That makes it more difficult to explain. And since I just thought of this, I may not even have a coherent explanation. When you used the computer, you saved something you did not yet own for your benefit so that might might be able to obtain it in the future. You finished your tasks earlier so that you might have other use for the time yet to come. Instead of finishing your tasks at 2:00, you finished them at 1:00 and could look forward to the time you were about to get, but hadn’t yet gotten (you could die at 1:01). The time you saved was not yet yours.
You know what amazes me? A ten year old native speaker probably makes this distinction automatically, but a group of adult native speakers can’t figure out why.
And if that is clear, you’ve probably heard about:
in the morning
in the afternoon
in the evening
at night.
Contemplate these two sentences:
“A vision came to me at night.”
“A vision came to me in the night.”