So, then, let's think about the difference between the two words (which word is spoken after the reason?) / Japanese Learning Support LLC | blog

So, let's look at the difference between the two words.

After stating a reason, is it more appropriate to use "therefore" or "and then" ?

" I definitely want to pass the N1 exam in 2026! That's why I'm starting private lessons ."

↑ Reason (motivation, etc.) ↑"Desu/Masu" [What you want to talk about]

This is how it is spoken. I think this is a Japanese pattern that you hear every day in various places.

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With busy days, before we knew it, we were already in the middle of January in 2026 and our normal lives were back to normal!

There are certainly times when I find studying and work difficult, but at the same time, I also feel like I have fun spending time with my classmates, teachers, and coworkers.

When I think back to last winter and wonder what I was doing a year ago, I feel like I've made progress, little by little, to get to where I am today.

From this cold season (January really is the month when the cold of midwinter bites!), it seems that we will be able to encounter many new events throughout the spring, summer, and autumn of this year!

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Let's study hard this year and make it a year of career advancement.

What kind of word is "then"?

Well, the first thing we'll think about today is the word that marks a reason: "kara".

Let's look at some example sentences.

● It's cold, so let's turn on the air conditioner.

Sorry, I'm going home early today. I feel like I have a bit of a cold.

Sentences like this, which mark the reason for something with the word "kara," are spoken in everyday speech.

I think this is one way of speaking Japanese that everyone can feel familiar with.

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So, what about the following Japanese?

" Sample (?) : It's cold . Let 's turn on the air conditioner. "

↑ "Sore" = "sakai" (cold). I tried splitting the first example sentence marked with * into two sentences and adding the connection "sorekara" (then) in the middle, but it still feels unnatural .

....

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The important thing to be careful about here is how you use the word "then."

■ "That"...can refer to something (topic) that has been discussed before! In the sample sentence, "cold" = "that."

■ "Because"... Mark the reason

When you mix these two words...

⇒ "sore" + "kara" = "and then"

(... Because of [something (=that: reason)] I told you about before , I am/will be...)

In the above situation:

⇒ "'A sentence for a reason'. 'Because of that (reason), 〜〜〜 is/is " ← What you want to talk about in terms of the result, etc.

I feel like I want to say it like this!

⇒(?) It's cold. Let's turn on the air conditioner.

...It is indeed a strange sentence.

If you feel something is strange (weird) then I believe that is the result of your daily studies .

Here are a few more examples:

Let's take a look at some similar sample sentences and find the unnatural parts!

→ (?) I was at work until 8 o'clock today, so I ended up coming home late.

[Reason] I was working until 8 o'clock today.

[What I want to talk about/Result] I ended up coming home late (+nda)

[Connections stated after the reason] ⇒ (◯) Therefore / (✘) Then

⇒ (◯) I worked until 8 o'clock today, so I got home late.

↑※ Use the word "therefore" to connect the two sentences (to connect the sentences).

First, state the reason. Use the word "therefore" as a connection between the two sentences, and then continue with the second sentence by explaining what you want to talk about (the result, etc.).

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The word "then" is not actually a "word that indicates a reason."

*[Caution!!] Remember that "sorekara" is a word used to ① indicate time or ② state additional things .

↓

Example:

● I have soccer club after school today, and then I'll probably get home around 7pm.

I take a shower every night, then read a little before going to bed.

I did a lot of shopping today. I bought sneakers and a cap. I also bought some hangers and took my jacket to the dry cleaners.

↑※This is an example of a sentence using "soreko" as a connection. The top two are "time" and the last one is "addition." (It's exactly the same as the "addition" at a yakiniku restaurant. /● "I'd like salted tongue and kalbi, oh, and some Korean seaweed, please.")

＜Points!＞

The important thing is to think about the 'normal body'.

*Funtsu style: This is the simple form of a word. It can be said to be the original form. It is a word that is used at the end of "desu/masu" and does not have the mood of being spoken as a sentence. → Example: It's raining ⇒ "It's raining" / Taberumasu ⇒ "Taberu", etc. (Details of the "Funtsu style" will be omitted in today's article.)

Since "sore" is a noun , "sore da " is usually the simplest form. ( Sore da / Sore janai / Sore datta / Sore ja kanakatta)

Now, let's mark this plain form "sore da" with "kara" and use the word "sore dakara" in the connection.

⇒ (◯) I worked until 8 o'clock today. That's why I got home late.

This example sentence (although it may seem a bit long-winded) is correct Japanese .

"Sore" + "da" ⇒ The word "sore da" means that you are talking about "something" that is the reason .

It feels like a small difference of just one hiragana character, "da."

However, by attaching "da" to "sore",

Something (/topic) we talked about before + da = [That is] (※That is)

In this way, you will be able to speak as "information." *You can also say it is in the form of a "sentence." It changes from a "sign" called a word to a "sentence."

It was important to create a solid block of words that was complete in terms of information (i.e., the size of a sentence) .

Therefore , using "that's why" is correct Japanese as a connecting phrase after stating the reason.

(However, in general speaking, I think it's best to simply use "dakara" (because) in cases like this as a connecting word between sentences.)

Let's summarize what we've covered so far.

■ "Then": A word for time, a word that adds other things

For example: I will finish my work by 12 o'clock, and then we can go to lunch together.

Example: I'd like a large portion of basil pasta, please. And a Caesar salad, too!

■ "Because" - A connecting phrase used after the reason

Example: (Today, I have an important meeting until 1:30 PM.) So , could you please wait a little while for lunch? (This might seem a bit off-putting. I think you should add some context.)

■ "Therefore": A connecting word placed after a reason . *It simply means to recommend something .

Example: I have a meeting until 1:30pm, so could you wait a little while for lunch?

(※↑This example feels simpler and more natural than the one above.)

"Sore" (as in the example sentence above) is a word that repeats a topic that was previously discussed, which is why it feels 'persistent'.

Use "that's why" when you want to summarize a long reason.

※Bonus: Examples of sentences using "that's why"

● There was an accident, so the rush hour was really bad today. I couldn't move, so I could fall asleep standing up on the train... And of course I couldn't take my smartphone out of my pocket... So I couldn't contact anyone.

● They say that moderate stress is motivation to find meaning in life, but working too hard, or studying too much can put a huge strain on not only your mind but also your health. In this busy modern world, just living your normal daily life can be overwhelming with so many things to think about, and stress can lead to all kinds of illnesses. Health is key to life. That's why I think it's okay to have fun and hobbies, to be carefree even if you don't have a lot of money, and to enjoy a drink.

● I understand how you feel, but you're still young, so don't rush through life. As the old saying goes, "It takes three years to warm a cold stone." Everything has its own history, and it's what creates the "present." That's why patience is important, and the relationships you build are precious.

↑ In a word of this size, saying "that's why" seems natural. However, it doesn't seem like something you'd use that often in your daily life, so remember to simply use "that's why" to connect two sentences that show the reason .

That's all for today's study.

We looked at some examples to confirm that "then" is a way of speaking that indicates "time (or "addition")" using the theme of "and then," which is often used incorrectly in relation to "reason," and that it is a form of sentence that conveys something after stating a reason.

I would be very happy if you could use this as a reference for tips when speaking Japanese.

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