Learn Hardcore Chinese: wǒ hē kāfēi de shíhou bù xǐhuan jiā táng. - When I drink coffee, I don’t like to add sugar.

[When I drink coffee] [I don’t like adding sugar] (original)
– Emphasizes the situation first.
I don’t like [adding sugar when I drink coffee]. (alternative)
– Emphasizes the dislike first.

But you cannot break up 喝咖啡的时候 itself; that chunk should stay together.

Why is it 不喜欢 and not 没喜欢?

不 and 没(有) are different:

不 – used for:
- general truth / habits / preferences
- future or planned actions
- “not” in a neutral or regular sense
没(有) – used for:
- past actions that did not happen (“didn’t …”)
- existence/possession (没有 = “don’t have / there isn’t”)

In your sentence:

不喜欢 = “(in general) don’t like”
没喜欢 is basically wrong in standard Mandarin; you rarely say that.

If you were focusing on not adding sugar on a specific occasion, you’d say:

我喝咖啡的时候没加糖。 – When I drank coffee (that time), I didn’t add sugar.

Here the verb for 没 is 加, an action verb, not 喜欢.

Why is there no past tense marker like 了? How do I know if this is past or present?

Chinese doesn’t mark tense (past/present/future) the way English does. The sentence:

我喝咖啡的时候不喜欢加糖。

by default expresses a habitual preference, like:

“When I drink coffee, I don’t like adding sugar.”
or “I don’t like sugar in my coffee.”

It’s about what you generally do, not one specific time.

If you want to make it clearly about a specific past event, you change the verbs, not by adding a general “past tense,” but by using aspect markers and time words:

昨天我喝咖啡的时候没加糖。
Yesterday, when I had coffee, I didn’t add sugar.
刚才我喝咖啡的时候不想加糖。
Just now when I was drinking coffee, I didn’t feel like adding sugar.

So: context and extra words (like 昨天, 刚才, 了, 过, 没/没有) tell you if it’s past, present, or future.

What is the difference between 加糖 and 放糖? Could I say 放糖 here?

Both 加糖 and 放糖 can be used when talking about putting sugar into something, but there are nuances:

加糖
- literally “add sugar”
- sounds a bit more neutral or “formal”
- common in menus, options, or instructions
- e.g. 这杯咖啡要不要加糖？ – “Do you want sugar in this coffee?”
放糖
- literally “put sugar (in)”
- often heard in casual spoken Chinese
- e.g. 帮我放点儿糖。 – “Put a bit of sugar in for me.”

In your sentence, both are OK:

我喝咖啡的时候不喜欢加糖。
我喝咖啡的时候不喜欢放糖。

加糖 is a bit more common in this kind of general preference sentence, but 放糖 wouldn’t sound wrong.

Do I need a measure word, like 一杯咖啡 instead of just 咖啡?

It depends what you want to emphasize:

我喝咖啡的时候不喜欢加糖。
Literally: “When I drink coffee I don’t like adding sugar.”
– General statement about coffee as a drink; natural and very common.

If you’re talking more concretely about a specific cup:

我喝一杯咖啡的时候不喜欢加糖。
– “When I drink a cup of coffee, I don’t like adding sugar.”

Usually, when you talk about general habits/preferences, you can just say 喝咖啡 without a measure word, like:

我喜欢喝茶，不太喜欢喝咖啡。
他每天喝咖啡。

Why is it 我喝咖啡的时候不喜欢加糖, not 我喝咖啡的时候喜欢不加糖?

Both are grammatically possible, but they focus on slightly different things:

我喝咖啡的时候不喜欢加糖。
- Directly says what you don’t like doing: adding sugar.
- This is the most natural, straightforward way to express this idea.
我喝咖啡的时候喜欢不加糖。
- Literally: “When I drink coffee, I like not adding sugar.”
- Grammatically OK, but feels a bit awkward or over-logical in everyday speech.
- It sounds like you’re treating 不加糖 (“not adding sugar”) as a “thing” you like.

Native speakers strongly prefer sentence 1 for ordinary conversation.

Can I omit 我 in the second part and say: 我喝咖啡的时候不喜欢加糖 vs 我喝咖啡的时候，我不喜欢加糖?

Both are possible.

我喝咖啡的时候不喜欢加糖。
- One smooth sentence, very natural.
- 我 is understood as the subject of both parts.
我喝咖啡的时候，我不喜欢加糖。
- Repeats 我.
- Grammatically fine; sometimes used to add a slight pause or emphasis.
- A bit more “choppy” in speech; you might use it for clarity in long or complex sentences.

In short, version 1 (no second 我) is more typical and sounds smoother here.

What exactly does 时候 mean in this sentence? Can I omit 时候?

时候 means “time / moment / when (…time)”.

我喝咖啡的时候
literally: “the time when I drink coffee”

If you drop 时候, you get:

我喝咖啡不喜欢加糖。

This is still grammatical and understandable. It now reads more like:

“When I drink coffee I don’t like adding sugar,”
or simply “I don’t like sugar in my coffee.”

Difference:

with 时候 – explicitly frames it as a time clause: “When I drink coffee …”
without 时候 – slightly more compact, sounds like a direct statement of preference.

In everyday conversation, both forms are used; 时候 just makes the “when” relationship crystal clear.

Why isn’t there a 在 before 喝咖啡 (like 在喝咖啡的时候)?

You can say:

我在喝咖啡的时候不喜欢加糖。

but it’s used in a slightly different way.

我喝咖啡的时候
– “When I drink coffee / when I have coffee” (neutral, general, habitual)
我在喝咖啡的时候
– “When I am (in the middle of) drinking coffee”
– emphasizes the ongoing process (“while I’m drinking coffee”)

In this sentence about a general preference, the simple form 我喝咖啡的时候 is more natural.
You’d more often use 在 … 的时候 when you really want to highlight an action happening during another action.

What are the tones and common pronunciation details for 不喜欢 and 喜欢?

Tones:

不 – 4th tone: bù
喜 – 3rd tone: xǐ
欢 – written as 1st tone huān, but in 喜欢, 欢 is usually pronounced neutral tone in everyday speech: xǐhuan

Tone sandhi for 不:

不 changes from bù (4th) to bú (2nd) before another 4th-tone syllable.
Example: 不是 búshì

In 不喜欢:

The next syllable xǐ is 3rd tone, not 4th, so 不 stays bù:
- bù xǐhuan

So you say: bù xǐhuan, with huan being light/neutral.

Could I say 我不喜欢喝咖啡加糖 instead? Is that the same meaning?

You can say:

我不喜欢喝加糖的咖啡。 – natural and common
literally: “I don’t like to drink coffee that has sugar added.”

But:

我不喜欢喝咖啡加糖 (without 的) sounds off and is not standard.

Why?

When you want to modify 咖啡 with 加糖, you generally need 的:
- 加糖的咖啡 – coffee with sugar
- 不加糖的咖啡 – coffee without sugar

So correct alternatives to express a similar idea are:

我不喜欢喝加糖的咖啡。 – I don’t like drinking coffee with sugar.
我喜欢喝不加糖的咖啡。 – I like drinking coffee without sugar.

Your original:

我喝咖啡的时候不喜欢加糖。
focuses on the action of adding sugar, not on the type of coffee.

Could I use 爱 instead of 喜欢, like 不爱加糖?

爱 and 喜欢 both can mean “like,” but they’re used a bit differently:

喜欢 – neutral “like / enjoy”; very common for preferences:
- 我喜欢喝咖啡。
- 他不喜欢加糖。
爱 – literally “love”; in daily speech it can also mean “really like / be fond of,” or sometimes “tend to / be in the habit of”:
- 我爱喝咖啡。 – I love / really like drinking coffee.
- 他爱迟到。 – He tends to be late.

In your sentence, 不爱加糖 is understandable and not wrong, but:

不喜欢加糖 is more neutral and standard for general preferences.
不爱加糖 can sound a bit more colloquial, like “I’m not into adding sugar / I don’t go for sugar.”

For learners, 喜欢 / 不喜欢 is the safest and most broadly appropriate choice here.