Word “变” (biàn) means “to change” or “to become.”

• 天气变冷了。
  (Tiānqì biàn lěng le.)
  The weather has turned cold.
• 你怎么变瘦了？
  (Nǐ zěnme biàn shòu le?)
  How did you get thinner?
• 他最近变得很安静。
  (Tā zuìjìn biàn de hěn ānjìng.)
  He’s become very quiet recently.
• 我手机信号变差了。
  (Wǒ shǒujī xìnhào biàn chà le.)
  My phone signal got worse.
• 事情突然变复杂了。
  (Shìqíng tūrán biàn fùzá le.)
  Things suddenly became complicated.
• 你变聪明了！
  (Nǐ biàn cōngmíng le!)
  You’ve become smarter!
• 他生病后性格变了。
  (Tā shēngbìng hòu xìnggé biàn le.)
  His personality changed after he got sick.
• 颜色变浅了一点。
  (Yánsè biàn qiǎn le yīdiǎn.)
  The color has become a bit lighter.
• 我开始变得紧张。
  (Wǒ kāishǐ biàn de jǐnzhāng.)
  I’m starting to feel nervous.
• 世界每天都在变。
  (Shìjiè měitiān dōu zài biàn.)
  The world is changing every day.

Tip: 变 is 4th tone (falling tone) → start high and drop sharply. In fast speech, it may sound a bit softer but still falling.

1. 天气变冷了。 (Tiānqì biàn lěng le.)

• 变 → strong, falling, almost like a small “snap” in your voice.
• Emphasize it because it shows the change in weather.

1. 你怎么变瘦了？ (Nǐ zěnme biàn shòu le?)

• 变 → quick, 4th tone, before “瘦” (also 4th tone). Don’t merge the tones; let the first fall clearly.

1. 他最近变得很安静。 (Tā zuìjìn biàn de hěn ānjìng.)

• 变 → pronounced clearly; “得” after it softens the sentence, so don’t rush 变.

1. 我手机信号变差了。 (Wǒ shǒujī xìnhào biàn chà le.)

• 变 → fall strongly; “差” also 4th tone, so there’s a natural double-fall rhythm here.

1. 事情突然变复杂了。 (Shìqíng tūrán biàn fùzá le.)

• 变 → emphasize because “复杂” is the new state. Native speakers often pause slightly after 变.

1. 你变聪明了！ (Nǐ biàn cōngmíng le!)

• 变 → strong, short fall; “聪明” is the effect, so 变 is like a “marker” of change.

1. 他生病后性格变了。 (Tā shēngbìng hòu xìnggé biàn le.)

• 变 → softer if speaking casually; in careful speech, still fall sharply.

1. 颜色变浅了一点。 (Yánsè biàn qiǎn le yīdiǎn.)

• 变 → clear 4th tone, “浅了” softens the overall sound; make the fall noticeable.

1. 我开始变得紧张。 (Wǒ kāishǐ biàn de jǐnzhāng.)

• 变 → start slightly higher and drop; “紧张” shows the effect, so 变 marks the beginning of the change.

1. 世界每天都在变。 (Shìjiè měitiān dōu zài biàn.)

• 变 → very natural, often pronounced softer and shorter in fast speech, but still falling. This is a common spoken style.