yǔqí yòng bù duì de zīshì, bùrú wèn jiàoliàn.

与其……不如…… is a very common pattern meaning:

• rather than A, it’s better to B
• instead of A, it would be better to B

So here, the sentence is saying that asking the coach is a better choice than using the wrong posture.

The pattern is:

• 与其 + option A
• 不如 + option B

Usually, A is the less desirable choice and B is the recommended one.

They work together as a set.

• 与其 introduces the first option: the one being rejected or seen as less good
• 不如 introduces the better option

So the structure is not random. It is a fixed comparison pattern:

与其 A，不如 B

If you remove one part, the sentence may become incomplete or sound unnatural in this particular structure.

Yes. Chinese often leaves out the subject when it is obvious from context.

This sentence does not explicitly say 你, 我们, or 人们, but depending on context it could mean:

• you should ask the coach
• we should ask the coach
• one should ask the coach

In advice sentences like this, leaving out the subject is very common.

Literally, it means something like:

• use an incorrect posture
• use the wrong form
• adopt a wrong position

In exercise, sports, or training contexts, 姿势 often means posture, form, or body position.

The verb 用 normally means to use, but in context it can mean to use/adopt a certain method or posture. So it sounds natural enough in a coaching or physical training context.

All three can work, but they have slightly different feelings.

• 不对的姿势 = the wrong posture / a posture that isn’t right
  
  • very natural in everyday speech
• 错误的姿势 = an erroneous posture / wrong posture
  
  • a bit more direct and stronger
• 不正确的姿势 = incorrect posture
  
  • more formal or textbook-like

So 不对的姿势 sounds conversational and natural, especially in spoken advice.

的 links a descriptive phrase to a noun.

Here:

• 不对 = not correct / wrong
• 姿势 = posture
• 不对的姿势 = the wrong posture / an incorrect posture

So 的 works a bit like the link between wrong and posture in English.

A simple way to think about it is:

[description] + 的 + [noun]

Both are possible, but they feel slightly different.

• 问教练 = ask the coach
  
  • direct, simple, neutral
• 问一下教练 = ask the coach briefly / ask the coach for a moment
  
  • softer and a little more conversational

In a general statement of advice, the plain verb 问 is completely fine.

So:

• 与其用不对的姿势，不如问教练。 = straightforward advice
• 与其用不对的姿势，不如问一下教练。 = slightly softer advice

Because 去 is optional here.

• 问教练 focuses on the action: ask the coach
• 去问教练 adds a sense of go and ask the coach

Both can be correct, but they are not exactly the same in emphasis.

Compare:

• 不如问教练 = better to ask the coach
• 不如去问教练 = better to go ask the coach

Without 去, the sentence is a little more general and compact.

It is a little more formal or polished than very casual everyday wording, but it is still common and useful.

You will see 与其……不如…… in:

• conversation
• writing
• advice
• arguments
• essays

It is not overly stiff, but it does sound more structured than very casual alternatives.

For example, more casual ways to express a similar idea might be:

• 不要用不对的姿势，最好问教练。
• 如果姿势不对，不如问教练。

But 与其……不如…… is a standard and very important pattern to learn.

They are pronounced differently because of tone sandhi.

• 不对 is pronounced bú duì
  because 不 changes from fourth tone to second tone before another fourth-tone syllable
• 不如 stays bù rú
  because 如 is second tone, not fourth tone

So in this sentence:

• 用不对的姿势 → yòng bú duì de zīshì
• 不如问教练 → bùrú wèn jiàoliàn

This is a very common pronunciation rule in Mandarin.

Yes. The best English word depends on context.

• posture = common if you are talking about body alignment
• position = possible, especially for a body pose or stance
• form = often very natural in sports, exercise, weight training, or martial arts

So if this sentence is about exercise or sports, form may sound especially natural in English:

• Rather than using the wrong form, it’s better to ask the coach.

If the focus is body alignment, posture also works well.

Yes, it is helpful because it separates the two halves of the pattern:

• 与其用不对的姿势
• 不如问教练

The comma marks a natural pause, just like in English when you say:

• Rather than doing A, do B.

In speech, you would usually pause slightly there too.