Learn Hardcore Chinese: wǒ dānxīn zìjǐ huì bǎ biǎogé tiáncuò. - I’m worried I might fill out the form incorrectly.

So 把 highlights the result on the form: it ends up being filled in incorrectly. It doesn’t translate as a separate word in English; it’s more of a grammatical marker that says “something will be done to this object, resulting in a change.”

Can I say 我担心自己会填错表格 instead? Is there a difference?

Yes, 我担心自己会填错表格 is also correct and natural.

Difference in feel:

我担心自己会把表格填错
– Slightly more focus on what happens to “the form” (being messed up).
– The ba-construction sounds a bit more vivid or concrete.
我担心自己会填错表格
– More neutral; feels like a simple “I’m afraid I’ll fill in the form incorrectly.”
– No special focus on the form as something you’re “doing something to.”

In most everyday situations, both are acceptable; many speakers would use them almost interchangeably.

Why do we use 自己 instead of just repeating 我?

自己 is a reflexive pronoun, roughly “myself,” “yourself,” “himself,” etc., depending on the context.

In this sentence:

Subject: 我 (I)
In the clause: 自己 refers back to 我

So 我担心自己会把表格填错 means “I worry that I myself will fill in the form incorrectly.”

Why use 自己 here?

It avoids repeating 我:
- 我担心我会把表格填错 is grammatically fine, but sounds a bit heavier or more direct.
It adds a slightly self-focused or introspective nuance: I’m worried about my own performance / ability.

You can also say:

我担心我会把表格填错。 (correct, a bit more blunt)
我担心会把表格填错。 (dropping both 我 and 自己; context must make it clear who “I” is)

What exactly does 会 mean here? Is it future tense, ability, or possibility?

Here 会 mainly expresses likelihood / possibility in the future, similar to English “will (probably)” or “might.”

In this sentence:

会 ≈ “will end up,” “might,” “may”
It does not mean “can” (ability) here.

So:

我担心自己会把表格填错。
≈ “I’m worried that I might/will fill in the form incorrectly.”

If you remove 会, it still works:

我担心自己把表格填错。

But with 会, it feels a bit more natural and clearly future-oriented: a thing that could happen.

What does 填错 mean, and how is it formed?

填错 is a verb + resultative complement:

填 = “to fill in,” “to fill out” (a form, blank, etc.)
错 = “wrong(ly), in error”

Together: 填错 = “to fill in (something) incorrectly / wrongly.”

This follows a very common pattern in Chinese:

写错 – write something wrong(ly)
说错 – say something wrong
看错 – see/read something incorrectly, misread
买错 – buy the wrong thing

So 填错表格 literally = “fill-wrong the form.”

Why is it 填错 and not 错填? Are both possible?

Both 填错 and 错填 exist, but:

填错 (verb + result) is much more common and natural in everyday speech, especially with objects like 表格.
错填 tends to sound more formal / written or appears in fixed phrases or technical contexts.

Structural difference:

填错表格: focus is “You filled in the form and the result is wrong.”
错填表格: focus is “You filled in the wrong form or misfilled the form” – can carry a nuance more like “mistakenly filled (this) form,” though in practice many people don’t distinguish them sharply.

In normal conversation about making a mistake on a form, 填错表格 (or 把表格填错) is the natural choice.

Can I leave out 会 or 把? How does the meaning change?

Yes, you can drop them, with small differences in nuance:

Drop 会:
- 我担心自己把表格填错。
  Still: “I’m worried I’ll fill in the form wrong.”
  Meaning basically the same; 会 just makes the “future possibility” feeling a bit clearer.
Drop 把:
- 我担心自己会填错表格。
  Still natural; slightly less emphasis on the form as an affected object.
Drop both 会 and 把:
- 我担心自己填错表格。
  Also understandable; a bit more compact and slightly more written in feel.

All four are grammatical. The original sentence is very natural and typical conversation-level Chinese.

Is 担心 a verb or an adjective here? How does its pattern work?

In this sentence, 担心 is used as a verb meaning “to worry (about), to be worried that…”.

Pattern here:

担心 + clause
我担心自己会把表格填错。
“I’m worried (that) I might fill in the form wrong.”

Other common patterns:

为/对 + something + 担心
- 我为你担心。 – I worry about you.
- 父母为孩子的安全担心。 – Parents worry about their children’s safety.
As an adjective-like predicate with 很:
- 我很担心。 – I’m very worried.
- 大家都很担心。 – Everyone is worried.

So it can act verb-like (worry about X / worry that …) and adjective-like (be worried).

Could I omit 自己 and just say 我担心会把表格填错?

Yes, 我担心会把表格填错 is natural and commonly used.

Nuance:

我担心自己会把表格填错。
– Explicitly says “I myself”; slightly more self-focused.
我担心会把表格填错。
– Subject (“I”) is understood from 我担心, so 自己 is not necessary; feels a bit more compact and conversational.

In most everyday contexts, 我担心会把表格填错 sounds very normal and no less clear.

Is this sentence formal or informal? In what situations would I use it?

我担心自己会把表格填错。 is neutral in style.

You can use it:

In casual conversation:
- Talking to friends or family when filling in applications, visa forms, exam forms, etc.
In polite or semi-formal settings:
- Talking to a clerk, teacher, or colleague:
  这个表格有点复杂，我担心自己会把表格填错。
  “This form is a bit complicated; I’m worried I might fill it in wrong.”

It’s appropriate almost anywhere; it doesn’t sound slangy or overly formal.