tā cónglái bú zài wǎnshang hē kāfēi, juéde kāfēi tài kǔ, hē wán yǐhòu yě shuìbuzháo.

This is a very common pronunciation rule.

不 is normally fourth tone: bù. But when it comes right before another fourth-tone syllable, it changes to second tone: bú.

Here, 不 comes before 在 zài (fourth tone), so it becomes bú zài.

• bù hē → stays bù, because hē is first tone
• bú zài → changes, because zài is fourth tone

This is only a pronunciation change; the word is still written 不.

Yes. 从来不 means never or has never in a general sense.

Compare:

• 他不在晚上喝咖啡 = He doesn’t drink coffee at night.
• 他从来不在晚上喝咖啡 = He never drinks coffee at night.

So 从来不 adds a stronger sense of habitual refusal or absence: not just doesn’t, but never does.

A useful pattern is:

• 从来 + 不 / 没 + verb

Examples:

• 我从来不抽烟。 = I never smoke.
• 他从来没去过北京。 = He has never been to Beijing.

Yes, you often can.

In Chinese, time words can often appear without a preposition:

• 他晚上喝咖啡。 = He drinks coffee at night.

Adding 在 gives a sense like during / at that time:

• 他在晚上喝咖啡。

Both are understandable, but in everyday speech, 晚上 without 在 is often more natural.

So in this sentence, 不在晚上喝咖啡 is grammatical, but many speakers would also naturally say:

• 他从来不晚上喝咖啡
• or more naturally, 他从来不在晚上喝咖啡 in a slightly more formal or careful style

Chinese word order usually places time information before the main verb.

A common order is:

subject + time/place + verb + object

So here:

• 他 = subject
• 在晚上 = time phrase
• 喝 = verb
• 咖啡 = object

That gives:

• 他从来不在晚上喝咖啡。

This is different from English, where time phrases can move around more freely.

觉得 means to feel or to think in the sense of having an opinion or impression.

Here:

• 觉得咖啡太苦 = (he) feels that coffee is too bitter

It introduces his personal judgment.

Common pattern:

• 觉得 + clause / adjective phrase

Examples:

• 我觉得很冷。 = I feel it’s cold.
• 她觉得这个电影很好看。 = She thinks this movie is very good.

In your sentence, the subject 他 is understood and doesn’t need to be repeated after the comma.

Because Chinese often omits subjects when they are already clear from context.

The sentence starts with 他, and everything after that still refers to him:

• 他从来不在晚上喝咖啡
• 觉得咖啡太苦
• 喝完以后也睡不着

In English, repeating the subject is often necessary. In Chinese, once the topic is established, repeating it can sound unnecessary.

You could repeat it for clarity:

• 他从来不在晚上喝咖啡，他觉得咖啡太苦，喝完以后他也睡不着。

But the original version is smoother and more natural.

太 + adjective means too ....

So:

• 太苦 = too bitter

This is different from 很苦, which means very bitter.

Compare:

• 咖啡很苦。 = Coffee is very bitter.
• 咖啡太苦。 = Coffee is too bitter.

So 太 expresses excess, often implying a negative result or complaint.

This is a very important Chinese structure.

完 after a verb is a result complement meaning finish / complete.

So:

• 喝 = drink
• 喝完 = drink up / finish drinking

Then 以后 means after.

So:

• 喝完以后 = after drinking it / after finishing drinking

This follows a common pattern:

verb + 完 + 以后

Examples:

• 吃完以后 = after eating
• 做完以后 = after finishing doing
• 看完以后 = after finishing watching/reading

Chinese often puts these action-completion elements directly after the verb, which is different from English.

Yes, but the meaning is slightly different.

• 喝了以后 = after drinking
• 喝完以后 = after finishing drinking

喝完 emphasizes completion more clearly. In this sentence, that works well because the idea is that once he drinks coffee, the effect continues and he cannot sleep.

So 喝完以后 sounds a bit more precise than 喝了以后.

Here 也 means also.

It links this second reason/result to the first one:

• coffee is too bitter
• and after drinking it, he also can’t sleep

So 也 does not always mean also in the sense of someone else too. It can also mean in addition / as well within the same person’s situation.

In this sentence, it adds another negative point about coffee at night.

睡不着 means cannot fall asleep.

This uses the pattern:

verb + 不 + result complement

Here:

• 睡 = sleep
• 着 zhāo = reach/succeed in the action here, meaning manage to fall asleep
• 睡不着 = be unable to fall asleep

This is different from 不能睡:

• 睡不着 = can’t fall asleep, even if you want to
• 不能睡 = cannot sleep, usually because you are not allowed to or it is not possible for some external reason

Examples:

• 我喝了咖啡睡不着。 = I drank coffee and can’t fall asleep.
• 现在不能睡。 = I can’t sleep now / I’m not allowed to sleep now / I must not sleep now.

Because 着 has several pronunciations and meanings in Chinese.

Common ones include:

• zhe: ongoing state, as in 看着
• zháo: succeed in reaching something, as in 睡着
• zhuó and zhāo in other words/usages

In 睡着, 着/著 zháo means something like manage to enter that state. So:

• 睡着 = fall asleep
• 睡不着 = can’t fall asleep

This is one of those cases where the pronunciation must be learned together with the word.

Yes, it is the same character, but the pronunciation and meaning change depending on the word.

• 觉得 = juéde = to feel / think
• 睡觉 = shuìjiào = to sleep

This is very common in Chinese: one character can have multiple pronunciations and meanings in different words.

So you should learn the whole word, not just the single character by itself.

In 觉得, 得 is usually pronounced in a neutral tone: de.

So the word is said as:

• juéde

This is just the standard pronunciation of the word 觉得. Many common two-syllable words in Mandarin have a neutral second syllable.

It is better to memorize 觉得 as one unit rather than analyzing 觉 and 得 separately every time.

It is one sentence made of several connected clauses:

1. 他从来不在晚上喝咖啡
2. 觉得咖啡太苦
3. 喝完以后也睡不着

Chinese often links related ideas with commas instead of breaking them into multiple short sentences.

In English, you might naturally split this up more. In Chinese, this kind of clause chaining is very normal, especially when all parts describe the same subject and topic.

Yes. The original sentence is correct, but many speakers might say it a little more simply, for example:

• 他从来不晚上喝咖啡，觉得太苦，而且喝完以后也睡不着。
• 他从来不在晚上喝咖啡，因为觉得咖啡太苦，而且喝完以后也睡不着。

Possible changes:

• omit 在
• omit the second 咖啡 if context is obvious
• add 因为 or 而且 to make the logic more explicit

But the original is still a good learner sentence because it clearly shows several useful grammar patterns.

A few very useful ones appear here:

• 从来不 + verb = never do something

  • 他从来不喝酒。

• 在 + time = at/during a time

  • 在晚上
  • though often the time word can appear without 在

• 觉得 + clause/adjective = feel/think that...

  • 觉得咖啡太苦

• 太 + adjective = too ...

  • 太苦

• verb + 完 = finish doing

  • 喝完

• ...以后 = after...

  • 喝完以后

• verb + 不 + result complement = cannot successfully do something

  • 睡不着

If you can recognize those patterns, this whole sentence becomes much easier to understand.