You are an AI assistant tasked with analyzing a passage of text to insert retrieval tokens and identify Prefix-intent (PI) and Key Factual Information (KFI). A Prefix-Intent (PI) should be a piece of text that should precede factual information, it must not be only 1 or 2 words. Key Factual Information (KFI) should be meaningful and include important details.

Your goal is to insert a  <|retrieval|> token after it is clear what the intent of the text is (e.g., "The president of the USA is"), but  before the key factual information is stated (e.g., "Joe Biden"). Whenever there is a <|retrieval|> token, we will retrieve the key factual information.

Here is the passage you will be working with:

<passage>
elements of a People's Army of Vietnam (PAVN) regiment reported to be operating in Thừa Thiên-Huế Province. The results were inconclusive with 8 VC killed while Marine losses were eight killed and 9 wounded. The 9th MAB provided Battalion Landing Team (BLT) of 1st Battalion, 26th Marines for Operation Deckhouse IV from 15–18 September 1966. The 9th MAB's Marines killed over 200 PAVN soldiers from 90th Regiment with the loss of 36 Marines. During the rest of the year, the 9th MAB and its units were stationed off the northern coast of South Vietnam in order to provide force for the defense of Vietnam Demilitarized Zone in case of emergency. 1967 BG Louis Metzger assumed command of the 9th MAB on 4 January 1967 and led it during Operation Deckhouse V in Bến Tre Province a few days later. The Battalion Landing Team 1/9, now assigned to the 9th MAB, took part in the operation, but due to forewarning, the VC left the area before the attack. The units of 9th MAB killed only 21 VC and lost 7 Marines. III Marine Amphibious Force (III MAF) launched Operation Desoto on 27 January 1967 against known VC strongholds in the region. The 9th MAB launched the Operation Deckhouse VI on 16 February in order to disrupt enemy movement in the vicinity of Sa Huynh salt flats, search northward in the Nui Dat area, and, finally, link up with the 3rd Battalion, 7th Marines, then operating around Nui Dat in Operation Desoto. BLT 1/4 confirmed the presence of VC in the area, but enemy concentrated only on delaying and harassing tactics. BLT 1/4 destroyed 167 fortifications and captured 20 tons of assorted supplies during the 32 days of Phase I of Operation Deckhouse VI. Though there never were any major contacts, the BLT claimed 201 VC killed during this period; only 6 Marines died. On February 27, Phase II of Deckhouse VI started, but there was only occasional contact with the enemy and intermittent sniper fire marked the only enemy reactions. In the six days required to accomplish the Phase II, the battalion killed 78 more VC, destroyed 145 fortifications, and captured an additional five tons of supplies. Similarly, as in Phase I, 6 Marines died. Because of a growing threat to Firebase Gio Linh, III MAF launched Operation Beacon Hill on 20 March 1967. BLT 1/4 and Marine Helicopter Transport Squadron 363 were ordered for the mission. The contact with the enemy was light until March 21, when the BLT 1/4 engaged about 80 PAVN troops, killing 14 of them. The next day the battalion made contact again between Gio Linh and Con Thien. After a stiff fight the PAVN, apparently a company, withdrew leaving 43 bodies behind. Progress during both days was slow because the PAVN laced their positions with connecting tunnels which required detailed search. On 26 March, after two days of air and artillery preparation, BLT 1/4 broke through two well-prepared defensive trench lines and cleared the interconnecting tunnel system. The PAVN subsequently withdrew and only sniper fire and minor rear guard actions slowed the advancing Marines. The operation ended on April 1 and BLT 1/4 suffered 29 Marines killed and 230 wounded. The PAVN lost 334 men. Following Operation Beacon Hill, 1/4 Marines was transferred back to the 3rd Marine Division and 9th MAB's Special Landing Force (SLF) was reorganized into twin concept: SLF Alpha, which consisted of HMM-263 and the 1st Battalion, 3rd Marines and SLF Bravo formed with 2nd Battalion, 3rd Marines and HMM-164. The landing exercise at Kin Blue Beach, Okinawa followed during April
</passage>

Follow these steps to complete the task:

1. Inserting retrieval tokens:
   a. Read through the text carefully.
   b. Identify potential Prefix-Intent (PI) sections that consist of a single intent and could serve as a search query. You must not modify the prefix intent and it MUST be part verbatim in the passage. It cannot be single or only a few words.
   c. For each identified PI, evaluate if the following sentence/subsentece that could serve as Key Factual Information (KFI).
   d. Insert <|retrieval|> tokens into the text AFTER the Prefix Intent (PI) and BEFORE key factual information is stated (KFI).
   e. Key Factual information should not intersect with Prefix Intent.

2. Identifying Prefix-Intent (PI) and Key Factual Information (KFI):
   a. For each <|retrieval|> token you've inserted, identify the preceding text as the Prefix-Intent (PI).
   b. Identify the following text, up to the next PI, as the Key Factual Information (KFI).
   c. Ensure that both PI and FI are short subsentences or phrases but not 1 or 2 words.

3. Insert <|start-PI|>,<|end-PI|>, <|start-KFI|>, <|end-KFI|>.
   a. For each identified Prefix Intent (PI), add a start and end special tokens (<|start-PI|>,<|end-PI|>) to quickly identify them.
   b. Do the same for the Key Factual Information (KFI) (<|start-KFI|>, <|end-KFI|>)
   c. Ensure that the very first PI in the passage is preceded by <|start-PI|>.
   d. Double-check that every PI and KFI is properly enclosed in these tags.

4. Describing ideal retrieved information:
   a. Given the Prefix-Intent (PI) and Key Factual Information (KFI), imagine an ideal retriever and enormous corpus. 
   b. Using the retriever and corpus, imagine that you can retrieve information given the Prefix-Intent.  
   c. Describe how that content should look like so it helps generating the Key Factual Information (KFI)


5. Reformulate the Prefix Intent if necessary: Reformulate it to not be impersonal. This means that if the subject it is not identified (e.g. it, he, she) you need to add the appropriate subject so the prefix-intent can be understood by itself. The subject should be changed from the previous information in the passage. Reformulated Prefix should not add any extra information or intent that is not mentioned in the original Prefix Intent.


6. Output format:
   For each pair of Prefix-Intent (PI) and Key Factual Information (KFI) you identify, provide the following output separating each example in a JSON list output. Ensure that it is actually a JSON.

   - Prefix_intent: [Write the Prefix Intent here]
   - Prefix_reformulated: [Write the Prefix Intent reformulated]
   - Key_Factual_Information: [Write the Key Factual Information here]
   - Verification: [Confirm that the KFI can be directly derived from the PI given a strictly connected context]
   - Ideal_Knowledge: [Describe how the ideal retrieved content should look to generate the KFI]
   - Explanation: [Briefly explain how the PI and KFI connect and why you chose to insert the <|retrieval|> token in that position]


7. Final step:
   After you have completed the analysis and provided outputs for all identified PI-KFI pairs, present the original passage with the <|retrieval|> tokens inserted in their appropriate positions

Here's an example of the expected output format:

Passage: Girmal Falls General This waterfall extends to a height of up to 100 feet, making it the highest waterfall of Gujarat. The picturesque beauty of this site makes it popular among visitors and people of the region alike. The water swiftly falls from a great height, creating a fog like condition that’s eye catching. The government of this state is working on many projects to make this place an ideal picnic spot and a tourist attraction. The fall comes to its best form at the time of monsoon and provides an immensely striking appearance. Some of the best natural features of Gujarat can be explored in this place. This place is a nice and refreshing retreat for any traveler.

```json
{ "results" : [
  {
    "Prefix_intent": "Girmal Falls General This waterfall extends to a height of up to",
    "Prefix_reformulated": "What is the height of Girmal Falls?",
    "Key_Factual_Information": "100 feet, making it the highest waterfall of Gujarat",
    "Verification": "The KFI directly provides the height information requested in the PI.",
    "Ideal_Knowledge": "A list of waterfalls in Gujarat, India, with their heights and rankings, specifically mentioning Girmal Falls as the highest at 100 feet.",
    "Explanation": "The PI introduces Girmal Falls and sets up a query about its height, while the KFI provides the specific measurement and its significance. The <|retrieval|> token is inserted to indicate where additional information might be needed to support the factual statement."
  },
  {
    "Prefix_intent": "The water swiftly falls from a great height, creating",
    "Prefix_reformulated": "What does the water falling from Girmal Falls create?",
    "Key_Factual_Information": "a fog like condition that's eye catching",
    "Verification": "The KFI directly describes the effect created by the falling water, as prompted by the PI.",
    "Ideal_Knowledge": "Detailed descriptions of the visual effects created by high waterfalls, including the formation of mist or fog-like conditions due to water droplets in the air.",
    "Explanation": "The PI describes the water falling and sets up a query about its effect, while the KFI provides the specific visual phenomenon created. The <|retrieval|> token is inserted to indicate where additional information might be needed to support the description."
  },
  {
    "Prefix_intent": "The fall comes to its best form at the time of",
    "Prefix_reformulated": "When does Girmal Falls come to its best form?",
    "Key_Factual_Information": "monsoon and provides an immensely striking appearance",
    "Verification": "The KFI directly answers when the waterfall is at its best and describes its appearance, as prompted by the PI.",
    "Ideal_Knowledge": "Information on the seasonal variations of Girmal Falls, highlighting the monsoon season's impact on water flow and visual appeal.",
    "Explanation": "The PI sets up a query about the best time to view the falls, and the KFI provides the specific season and describes the appearance. The <|retrieval|> token is inserted to indicate where additional information about seasonal changes might be needed."
  }],
"Updated_Passage":"<|start-PI|> Girmal Falls General This waterfall extends to a height of up to <|end-PI|> <|retrieval|> <|start-KFI|> 100 feet, making it the highest waterfall of Gujarat <|end-KFI|>. The picturesque beauty of this site makes it popular among visitors and people of the region alike. <|start-PI|> The water swiftly falls from a great height, creating <|end-PI|> <|retrieval|> <|start-KFI|> a fog like condition that’s eye catching <|end-KFI|>. The government of this state is working on many projects to make this place an ideal picnic spot and a tourist attraction. <|start-PI|> The fall comes to its best form at the time of <|end-PI|> <|retrieval|> <|start-KFI|> monsoon and provides an immensely striking appearance <|end-KFI|>. Some of the best natural features of Gujarat can be explored in this place. This place is a nice and refreshing retreat for any traveler."
}

```
8. Final check:
  a. Review the Updated_Passage to ensure all PIs and KFIs are properly tagged.
  b. Verify that the first PI in the passage starts with <|start-PI|>.
  c. Make sure there are no missing or misplaced tags.
 
Remember to analyze the entire passage, identify all relevant PI-KFI pairs, and provide the output for each pair as specified. After completing the analysis, present the original passage with the <|retrieval|> tokens inserted in their appropriate positions as part of a new key in the JSON file. Only Ouput the JSON File.