zhè gè dōngxi bú tài guì, wǒ xiān shìshi.

Chinese normally uses the pattern demonstrative + measure word + noun: 这 + 个 + 东西 = “this thing.”

• Saying 这个东西 is the safest, most neutral option.
• In casual speech you can drop the measure word and say 这东西; it’s common and natural.
• Don’t say 这件东西 unless you really mean “this piece/item” in a stylistic or specific context; for everyday speech, use 个 with 东西.
• You can also hear the colloquial pronunciation zhèi ge for 这个.

Tone sandhi: 不 (bù) changes to the second tone bú when it comes directly before a fourth-tone syllable.

• Here it’s before 太 (tài) (4th tone), so you say bú tài.
• More examples: bú shì (不是), bú duì (不对).
• Before 1st/2nd/3rd tones, 不 stays bù.

In Chinese, adjectives act like verbs (stative verbs) and can directly be predicates: 这个东西不太贵.

• For a simple positive statement, you typically add a degree adverb: 这个东西很贵 (not “是贵”).
• You can say 这个东西不是太贵, but it has a slightly different tone (often a polite, downplaying “isn’t too…”).

先 (xiān) means “first/first of all” (do this before other actions). It’s an adverb that goes before the verb phrase: 我先试试.

• Pattern: 先 A，再/然后 B (“First A, then B”).
• Putting 先 after the verb (我试试先) is nonstandard in Mandarin (it’s a Cantonese-like order).

Context often makes the object obvious, so 我先试试 is fine at a shop. If you include it, place it after the verb phrase:

• 我先试试这个。
• With “put” structure: 我先把这个试试。
  Avoid patterns like “试这个试.”

Use a question or add softening particles:

• 我可以试试吗？ / 能试一下吗？
• For clothes: 可以试穿吗？ / 我可以试一下这件吗？
• You can also say: 我先试试吧。 (self-suggestion, softer)

Chinese often links clauses with a comma (parataxis). The comma here separates reason → action. You can add connectors:

• 这东西不太贵，所以/那我先试试。
• 这东西不太贵，然后我先试试。 (then)
  Leaving just the comma is very natural.

It’s okay, but more precise is better. Use the right measure word and noun:

• Tops/dresses: 这件衣服不太贵，我先试穿一下。
• Pants/skirts: 这条裤子/裙子…
• Shoes: 这双鞋…
• Hat: 这顶帽子…