Subtle difference

[JbhB682]

Hi Experts - just curious, what is the difference between these 3 sentences

(I) Present tense --- Most people cook dinner by 10 pm

(ii) Present perfect - Most people have cooked dinner by 10 pm

(iii) Past perfect ----- Most people had cooked dinner by 10 pm

[JbhB682]

(a) the 1st -- is a general truth

(b) not sure if its okay to use present perfect with time marker - by 10 pm ?

I say this because normally present perfect is used for a past experiences that continue into the present or remain true in the present.

I think we can use this sentence only if we know for sure that sentence (ii) is true today (as of Feb 24th 2022)

(c) I think the 3rd is used when we want to stress the cooking is fully completed by 10 pm

We can use ths sentence if we know for sure that sentence (iii) is true today (as of Feb 24th 2022) or if sentence (iii) took place in the past (say in the year 2018 for example...)

[Whit Garner]

Hi Experts - just curious, what is the difference between these 3 sentences <br data-uw-styling-context="true"><br data-uw-styling-context="true">

<br data-uw-styling-context="true">(I) Present tense --- Most people cook dinner by 10 pm<br data-uw-styling-context="true"><br data-uw-styling-context="true">(ii) Present perfect - Most people have cooked dinner by 10 pm<br data-uw-styling-context="true"><br data-uw-styling-context="true">(iii) Past perfect ----- Most people had cooked dinner by 10 pm <br data-uw-styling-context="true">

There are several uses for most verb tenses!

While "present" tense can certainly be used to talk about something happening right now, it can also be used to indicate something that is universally true; that is what is happening in this example.

"Present Perfect" had a LOT of different meaning. As the other poster mentioned, it can be used to indicate something that happened in the past but is still true now / happening now (usually with an -ing ending to indicate the "ongoing" nature of it). It can also be used for something that happened in the recent past, even though it isn't happening anymore (we have already eaten dinner). Again, as the other poster mentioned, if it is filling this role, we wouldn't use a fixed time in this way. But in your example, this would only logically work as something that happened in the past but that makes it a "true" fact about things. Here it would be as if you're saying that at some point in time, most people have cooked dinner by 10pm. Much like the example "Many people have cooked pasta." They have cooked pasta at least once in their lives.

Your last example, "past perfect," is about something that happened before another event in the past. This is represented by a different verb in the sentence in past test, "He brought (past) her dinner, but she had eaten (past perfect) already", or a time stamp in the past, "Most people had dinner by 10pm" (assuming that the 10pm in question is in the past.

Hope this helps!