Learn Hardcore Chinese: tā yìzhí hěn nǔlì, suǒyǐ xiāngxìn zìjǐ de chéngjì huì yuè lái yuè hǎo. - She has always worked hard, so she believes her grades will get better and better.

In Chinese, when an adjective functions as a predicate (describing the subject, like “is happy / hardworking”), a degree adverb like 很 is usually inserted, even if it doesn’t strongly mean “very.”

So:

她很努力。
literally: She very hardworking.
practically: She is hardworking.

Without 很, 她努力 often sounds like “she puts in effort” (more verb-like) or can feel incomplete in everyday speech. 很 smooths it out and makes it sound like a natural description.

So 一直很努力 is: has always been hardworking.

Is 努力 here an adjective (“hardworking”) or a verb (“to work hard”)?

In 她一直很努力, 努力 is used as an adjective meaning “hardworking / diligent.”

You can also use 努力 as a verb:

她一直努力学习。 – She has always worked hard at her studies.

Compare:

她很努力。 – She is very hardworking. (adjective)
她努力工作。 – She works hard. (verb)

In your sentence, the structure 一直 + 很 + (adj) makes 努力 clearly adjectival.

Why is there no 她 before 相信? Shouldn’t it be 所以她相信…?

Chinese often omits a repeated subject when it’s clear from context.

Full form:

她一直很努力，所以她相信……

Because the second 她 is obvious (it’s the same “she”), it’s dropped:

她一直很努力，所以相信……

This is natural and common in spoken and written Chinese. If there were a risk of confusion about who believes, 她 would usually be kept.

What exactly does 自己 refer to here?

自己 is a reflexive pronoun, like “self” / “oneself.”

In this sentence, 自己 refers back to the subject 她. So 自己的成绩 means “her own grades.”

Key point: 自己 usually refers to the subject of the clause unless clearly marked otherwise. Here the subject (even though omitted) is still 她, so 自己 = 她自己.

Why is there a 的 after 自己: 自己的成绩? What is 的 doing here?

的 is linking a modifier to a noun, similar to the possessive ’s or “of” in English.

自己 = self
自己的成绩 = one’s own grades

Structure:

(possessor / modifier) + 的 + noun
Examples:
我的书 – my book
她的朋友 – her friend
他自己的想法 – his own ideas

So 自己的成绩 means “one’s own grades / her own grades.”

What is the role of 会 here? Does it mean “will” or “can”?

In this sentence, 会 mainly expresses a future likelihood: “will / be likely to.”

成绩会越来越好 = (the) grades will get better and better.

会 often conveys:

future tendency / prediction: 明天会下雨。 – It will (is likely to) rain tomorrow.
ability (can): 我会游泳。 – I can swim.

Here it’s prediction/expectation. You could say 成绩越来越好 without 会 in some contexts, but 会 makes the “in the future / as time goes on” idea clearer.

How does the pattern 越来越好 work? What does 越…来越… mean?

越来越 + adjective means “more and more + adjective,” showing gradual change over time.

So 越来越好 = “better and better / increasingly good.”

Structure:

越来越 + adj
- 越来越大 – bigger and bigger
- 越来越难 – more and more difficult

The characters:

越 = more
来 = coming (toward now)

Together they form a fixed pattern for gradual increase.

Could we say 会越来越好的成绩 instead of 成绩会越来越好?

You generally should not say 会越来越好的成绩 in this sentence. The natural pattern is:

[subject] + 会 + 越来越 + adj
→ 成绩会越来越好。 – The grades will get better and better.

Making 会越来越好 into an adjective phrase in front of 成绩 (like “the will-be-better-and-better grades”) is not how Chinese typically structures this idea. It sounds awkward and unidiomatic.

Keep 成绩 as the subject, and 会越来越好 as the predicate.

Why is 所以 used by itself? Don’t we normally see 因为…所以…?

You can have:

因为…，所以… – because…, therefore…
just 因为… – because…
just 所以… – therefore / so…

Here, the cause is expressed in the first clause without 因为:

她一直很努力 – She has always worked very hard.

Then 所以 introduces the result:

所以相信自己的成绩会越来越好。 – so she believes her grades will get better and better.

Both full and shortened forms are common:

因为她一直很努力，所以她相信……
她一直很努力，所以相信……

Is 成绩 only “grades,” or can it mean “achievements” more generally?

成绩 usually means:

School grades / exam scores / results
- 考试成绩 – exam results
- 学习成绩 – academic performance
Performance / achievements in a measurable way
- 工作成绩 – work performance, work results

In this sentence, with 自己 and 会越来越好, it most naturally refers to school grades or exam results, but in another context it could be broader “results/achievements.”

Could we just say 她相信自己会越来越好? What changes if we remove 成绩?

Yes, 她相信自己会越来越好 is a correct and natural sentence, but the meaning changes:

她相信自己的成绩会越来越好。
She believes her grades will get better and better.
她相信自己会越来越好。
She believes she herself will keep getting better (as a person, in life, in ability, etc.).

So the original with 成绩 is more specific: it’s about academic or measurable performance, not her whole self.

Why is there no 了 in 她一直很努力? Shouldn’t past actions take 了?

了 is not required for describing a state over a period of time like “has always been hardworking.”

一直 already shows continuity from the past up to now. The sentence is describing her general state/quality, not a completed single action, so 了 is unnecessary and would sound odd here.

Compare:

她一直很努力。 – She has always been hardworking. (state over time)
她努力了三个月。 – She worked hard for three months. (completed period, uses 了)

Your sentence focuses on her ongoing characteristic, not on finishing an action.

Is this sentence more written or spoken style? Would it sound natural in everyday conversation?

The sentence is perfectly natural in everyday spoken Mandarin and also fine in writing.

In spoken Chinese, someone might say:
- 她一直很努力，所以她相信自己的成绩会越来越好。
  or drop the second 她, as in the original.
In written Chinese (like a short essay about a hardworking student), the same sentence works well.

So it’s neutral and widely usable—neither overly formal nor too slangy.