Ant_222 wrote:
<<It is not clear to me.
Can you show some situations with both present and past backgrounds?>>
My reply: Because the context of our discussions contains Simple Present or Present Perfect, so it is a present background. In such background, we seldom use Past Perfect. Isn't this clear enough for you?
In a storybook, on the other hand, we don't use Present Perfect. All you can find is Past Perfect only. Is this not clear enough for you?
Or are you now arguing you cannot see whether it is a commentary or a storybook?
In past background, Past Perfect and Past Progressive express their time relations to Simple Past.
In present background, Present Perfect and Simple Past express their time relations to Simple Present.
In this case, we still can explain all the tenses merely by two notions of time: past and present.
I have long noticed the tenses in a commentary are different from those in a storybook. Sometimes, the two kinds of contexts may be fused into one, as a paragraph of story may be mentioned in the commentaries. However, as a whole, we won't have a big trouble in detecting whether the paragraph is present background or past background.
The structure <after + Simple Past> appears mostly in the present background, whose characteristic is that the context contains present tenses such as Simple Present or Present Perfect. This background is for commentaries, where we will compare the past with the present, so there are both past and present tenses. In this background there are mainly the three tenses: Simple Past, Present Perfect, and Simple Present.
The structure <after + Past Perfect> appears mostly in the past background. This background is for an recount of story, describing actions step by step, in a smooth flow. In this background there are mainly past tenses such as Simple Past, Past Perfect, and Past Progressive.
Below, we may try to see online where the sequences work. The examples are new for today.
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<after + Simple Past>
If on the web today you search exact match for "after he walked", you may notice the characteristic of the present background. The following examples are taken from the first and second resulting pages:
Ex1: Amy Goodman: Here is some of what Mordechai Vanunu said today right AFTER HE WALKED out of prison. Mordechai Vanunu: I am Mordechai Vanunu, the man behind the publicized article from October 5, 1986. The article was about Israel's.....
Ex2: Two thousand years AFTER HE WALKED the earth, Jesus of Nazareth remains one of the most talked-about and influential people who has ever lived. In the pages that follow, we explore his life, character, teaching and followers.....
Ex3: He only remembers that the day AFTER HE WALKED away, he sat in an airport, looked up at the television and watched Nolan Ryan throw his fifth no-hitter. They had been linked, Ryan and Clyde. They were both hard throwers from Texas.
Ex4: On March 18, 2003, a 20-year old male volunteer fire fighter (the victim) died AFTER HE WALKED into the path of a tractor-trailer truck..... The volunteer fire department has 20 active fire fighters and serves a population of approximately 2,500 in an area of about 8.5 square miles..... Since the incident occurred, the department has revised its standard operating procedures.....
Ex5: A lot of people would like to know what happened to Nicholas Berg AFTER HE WALKED out of Baghdad’s Fanar Hotel on 10 April. They say the 26 year-old American contractor was looking for a taxi when he walked off down the street and into.....
Ex6: In the years AFTER HE WALKED on the Moon, some of literature's biggest names - Stephen Ambrose and James Michener among them - pursued Armstrong's biography with no success. So how is it that a history professor who grew up in Fort.....
Ex7: Columbus- Four years AFTER HE WALKED on the Ohio State football team, John Conroy hugged his father after the Buckeyes' 17-10 defeat to Penn State on Saturday..... If starting right tackle Kirk Barton can't play against Michigan State - and he's still questionable with the knee injury he suffered in the first quarter at Beaver Stadium - freshman Alex Boone, not Conroy, is slated to start in his place.
== For most of the cases above, I didn't even need to click into the web pages to find out, but I still can see present tenses (Simple Present or Present Perfect) in them, so that I know they are present background. However, I did click into some pages to find out, and I admit I saw a writer uses "after he walked" in past background.
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<after + Past Perfect>
On the other hand, if we search exact match for "after he had walked", we may notice that the context in which the sequence is, is past background. The following examples are taken from the first resulting page. I did click into the web pages and recognize they are accounts of stories, so I believe the authors use Past Perfect automatically and correctly.
Ex1: AFTER HE HAD WALKED a little farther, Half-Chicken found the wind tangled in some bushes. "Good morning, Half-Chicken. Would you please untangle me, so that I can go on my way?" asked the wind. Half-Chicken untangled the branches.
Ex2: AFTER HE HAD WALKED some 200 miles on foot to the sea to collect salt illegally, the Viceroy started to relieve the punitive salt taxes and the government monopoly. Gandhi also strove to raise the status of untouchables, the caste whom.....
Ex3: AFTER HE HAD WALKED about the world for a long time, he entered into a dark forest, and walked for fourteen days, and still could not find his way out. Then it was once more evening, and he was so tired that he lay down in a thicket and.....
Ex4: AFTER HE HAD WALKED perhaps 10 feet, a stout man stepped between newsman at the edge of the crowd. He extended his right hand, which gripped a Colt .38-caliber revolver, and fired "a single fatal bullet into Oswald's abdomen," as the.....
Ex5: Foster Powell was another pedestrian who became well known AFTER HE HAD WALKED the 402 miles between London & Leeds in just 5 days and 15 hours. It can't go unnoticed that Barclay often interrupted his rigid training-program for boozing.....
== It is present background (because there is present tense), but Past Perfect is used in a past subordinate clause within another past subordinate clause, where Present Perfect is not normally used.
Ex5: So AFTER HE HAD WALKED the whole day, he too came at dusk to the King's palace. There stood the King out on the steps, and asked whither he was bound. "Oh," said Boots, "I'm going about seeing if I can hear of a place."
Ex6: AFTER HE HAD WALKED for a long time, he came to the courtyard of a royal palace, and as he felt weary, he lay down on the grass and fell asleep. Whilst he lay there, the people came and inspected him on all sides, and read on his girdle.....
== Instead of search for "walk", one may try other verbs like "after he had done/ seen/ worked/ etc." You may help check whether the theory of background is feasible or not.
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Ant_222 wrote:
«After Tim had left, I found the lost key. That IS why I couldn't give it back to him.» — here the sequence of actions is important. If Tim hadn't left before the key was found, he would have received it back.
My reply: Just because the example contains Simple Present IS, it is a comment, a present background. Therefore, Past Perfect is not suitable. Being important or evident is not the criterion to tell the difference between <after + Simple Past> and <after + Past Perfect>. No Adjectives or Meanings can explain tenses; only Time does.