A Person You Helped to Improve His or Her Fitness

Why this band

• LR“Nam's fitness improved a lot” — "Improved a lot" is a generic verb-plus-intensifier combination that could apply to almost any kind of progress, rather than a more specific phrase ("his stamina built up quickly," "he got noticeably fitter") that would better capture the particular improvement described afterward (playing a full game, losing weight). This generality functions as a topic sentence for the paragraph, with the specific evidence following separately, a common and acceptable pattern at Band 6.5 even though the summary phrase itself stays lexically plain.
• GRA“At first Nam was very slow and got tired after ten minutes, but I told him not to give up” — Two separate ideas — Nam's early struggle and the speaker's encouragement — are joined with a single "but," rather than being subordinated ("even though Nam was very slow at first, I told him..."). "Very" and "got tired" are both simple intensifier-plus-verb combinations, keeping the vocabulary plain even as the anecdote itself conveys a fairly specific coaching moment. This reliance on coordination over subordination for linking contrasting ideas is exactly the basic linking pattern the Band 6.5 grammar descriptor describes.
• FC“so our little badminton group is getting bigger” — This closing sentence reports a simple, ongoing observation (the group is "getting bigger") using the present continuous, wrapping up the story with a concrete, verifiable fact rather than a more reflective statement about what the experience meant to either the speaker or Nam. It's a functional, understated way to end a Part 2 answer, consistent with the direct, one-idea-at-a-time closing style typical of Band 6.5, where elaborating further isn't necessary to satisfy the task.

Why this band

• GRA“but I encouraged her to keep going at her own pace rather than comparing herself to me” — This sentence stacks a 'but'-coordinated contrast with an infinitive purpose structure ('encouraged her to keep going') and a 'rather than + gerund' comparison, all inside one sentence describing a specific coaching moment. A 6.5 answer would likely break this into two flatter sentences ('She was tired. I told her not to compare herself to me.'); a 7.5 answer might additionally front-load the contrast for emphasis. The combination here is accurate and unforced, matching 7.0's comfortable mix of simple and complex sentences, and it captures psychological coaching, not just a physical instruction.
• LR“out of breath” — 'Out of breath' is a fixed, everyday collocation used twice — first to introduce Mai's problem, later to mark her improvement — so the same natural phrase functions as a measurable before-and-after marker rather than a one-off description. A 6.5 answer might use a flatter phrase like 'very tired'; a 7.5 answer might vary the repetition with something more figurative. Reusing this exact phrase to bookend the story is a small coherence device as well as an accurate collocation, matching the flexible everyday vocabulary 7.0 calls for.
• FC“It's honestly been nice to see her build that habit up gradually” — This closing line shifts from reporting Mai's fitness results to the speaker's own response to watching the change unfold, with 'honestly' marking genuine spoken reflection rather than a rehearsed conclusion. A 6.5 answer would likely end by simply restating the outcome ('Now she is not tired anymore'); here 'build that habit up gradually' also frames the change as a process, adding interpretation on top of fact. That process-aware reflection is the developed coherence 7.0 targets, leading naturally into the detail about other colleagues joining.

Why this band

• LR“his energy is honestly on a different level compared to before” — 'A different level' is an idiomatic way of expressing a large, qualitative change that avoids the flatter, more literal alternative a lower-band answer would use, such as 'he has a lot more energy now.' Choosing this natural collocation, and softening it with the conversational filler 'honestly,' is the kind of precise, flexible vocabulary the Band 7.5 lexical target rewards over the plain comparative structures a 7.0 answer would rely on. Placing the phrase at the very end of the answer also gives it weight as a closing verdict on Quân's progress, summarising six months of specific detail in one confident, colloquial line.
• FC“I think seeing his progress kept me motivated as well.” — The sentence reverses the expected direction of the story — instead of only describing how the speaker motivated Quân, it notes that watching Quân's progress motivated the speaker in return — a reflective, slightly unexpected observation rather than a simple continuation of the narrative. That kind of two-way, self-aware insight is the evaluative depth the Band 7.5 coherence target rewards, where a plainer answer would likely stop at describing the other person's improvement. It also sets up the answer's closing line about the running group growing, reframing the whole story as a mutual, ongoing relationship rather than a one-directional favour.
• GRA“He admitted he'd been skipping meals and not moving much, especially after a busy period with lots of late-night coding sprints.” — The sentence opens with reported speech using the past perfect ('he'd been skipping meals'), then extends it with a prepositional phrase modified further by 'especially after a busy period with lots of late-night coding sprints,' stacking detail onto a single main clause rather than starting new sentences for each fact. Managing that much layered elaboration accurately, while keeping the reported-speech tense consistent throughout, is the varied complex grammar the Band 7.5 target rewards, going beyond the simpler reported statements a 7.0 answer would typically produce. The workplace-specific detail about 'coding sprints' also grounds the reported admission in a believable, specific cause.