When does omission of です constitute casual speech?

Question

In many textbooks, polite style speech is taught, which means です and ます endings are introduced, and used in many sentences.

However, I have encountered sentences with omissions, for example sentences which omit verbs. They may also end with particles. I think this is done to introduce vagueness, or simply to make the sentences shorter.

In what context do such omissions constitute not polite speech anymore, but plain speech? For example, in the drama Meguri Ai, Episode 8, there are some "incomplete sentences" that have differing levels of politeness (I have some context and sentences written here, but if more background is desired, the specific video segments are listed below - please visit https://youtu.be/mNOOEfpjuUM):

Video time: 02:35 - 03:30:

社員：おつり、いいから。 (plain)

A boss (社長, name 修二) is in the back of a taxi with his subordinate (社員), and the subordinate says this to the driver. Although polite forms were used with the driver up until that sentence, I feel that this sentence is in plain form as the subordinate feels superior to the driver due to a perceived difference in social status.

Video time: 11:25 - 11:45:

修二：じゃあ、早稲田まで。 (polite)
絵里（運転手）：この時間だと電車で行くほうが早いとおもいますけど。。。(polite)
修二：いいんです。行ってください。 (polite)

Apparently this sentence is still polite, according to my teacher. I am not sure why, though.

Video time: 12:53 - 13:10:

修二：そういうわけにはいかないんです。 (polite)
絵里（運転手）：どうして？ (plain)
修二：そいつにだけは、幸せになってほしいから。そうおもって２年前に別れたから。(plain)

Eri (絵里) asks どうして, which apparently is in plain style, and Shuuji (修二) replies in plain form with two occurrences of から without です.

There are many sources that state that ending with から is informal. However, まで is another particle, yet ending with まで without です (second bolded sentence) seems to leave the polite style speech unaffected. Again, どうして without です seems to be informal.

---

When does omission make sentences casual / plain? Examples would be greatly appreciated.

Answer 1

I think じゃあ、早稲田まで isn't polite but plain. じゃあ、早稲田まで行ってください and じゃあ、早稲田までお願いします would be polite.

Sentences without です, ます aren't polite, so the sentences that end with particles like 早稲田まで, ほしいから, and 別れたから aren't polite. And どうして？ isn't polite either because it's without です, ます.

I think omission of です, ます always makes sentences casual / plain.

Answer 2

In the French language, when I meet someone, I decide whether I am going to use the polite form or familiar form. I usually stick to one. I don't go switching back and forth between them.

In Japanese, people often switch back and forth all the time. This is very tough to learn, but there is no logical way to really learn it other than just to get a lot of experience with the language. It's not just a simple matter of polite or familiar forms. I would say that each way of using polite or informal speech has it's own feeling of a level of politeness or familiarity, and what is used may depend on the feeling that the speaker had at the time.

If you want to be strictly polite, always use "desu" and "masu". As with most languages, the risk you take is to come off as too stiff and alienate people with whom you could have been more familiar. It's when you have human relationships that fit into a certain gray area between formal and familiar where you see the most mixing of different levels of politeness/familiarity. Examples are the employee who is quite friendly with the boss and the sushi chef who is friendly with the customer.

"Masu" for some reason is more stiff and formal sounding than "desu". I use "desu" (usually softened with a "ne") with people who I just met who are around my age, but never "masu". I only use "masu" when speaking to staff of a store or people older than me whom I don't know.

"Karadesu" sounds very stiff and formal for some reason. "Desukara" doesn't sound any more stiff than using "desu" in general.

These omissions are not to introduce vagueness. I do think that the way Japanese is generally used is slightly more vague than how English is usually used, but don't listen to a lot of the beginners who harp on about Japanese being too vague because they actually just don't understand it.

Also, in the specific example of "じゃあ、早稲田まで," I don't know why, and maybe someone else can explain it, but adding "desu" would sound weird there.

When you said "I feel that this sentence is in plain form as the subordinate feels superior to the driver due to a perceived difference in social status," I think you're overthinking that.

As I imagine you have read, leaving out the masu and desu and using the familiar forms of verbs is, well, the familiar way. Do this with your friends. On occasion there are friends who use "desu" with me, but usually not. You might see two Japanese friends using "desu" together almost all the time. I don't pretend to understand it. I've never seen two friends using "masu" together.

Answer 3

It's because the terminal form of a sentence is shown.

おつり、いいから is a complete sentence and nothing is omitted after it. (Even if there is something, it's another sentence.) So you can tell it's plain.

じゃあ、早稲田まで and どうして lack the verbs and uncertain if they are plain or polite.

In the case of そいつにだけは、幸せになってほしいから。そうおもって２年前に別れたから, it is a noun phrase hiding the verb in the main clause だ or です i.e. "(it's) because ..." and you technically can't tell which it is. But it more often than not sounds omission from …から だ as is often the case with it, though there's a room to interpret it otherwise.

Answer 4

All the above answers seem accurate and helpful. But because none offer a definitive "black and white" rule, I think you can see that it often depends on the situation, the people involved, and the interpersonal dynamic.

In the first example "いいから" the speaker could have said "いいです", especially if the speaker was a woman. Or for both women and men, simply "おつり、いい". I put this in the category of standard scripted phrases that everyone uses naturally to avoid unnecessary conversational overhead.

For example, say you go down to Akihabara and ask one of the guys in those little parts shops if they have 10-ohm resistors. Even though you're a customer, they may just respond by saying "ない" to let you know they don't have any in stock. Crisp, clear, no fuss. Go to a department store in Ginza and look for a certain brand or model of a handbag or something, and the clerk would probably say "ございません". Depends on the situation.

"早稲田まで" fits that pattern too. Minimal verbiage to communicate the required information to initiate the transaction. "早稲田までおねがいします" would be fine too. And, "早稲田までです" wouldn't be strange either.

By the time you get to the 3rd example: "どうして" and "、、、から” I think the 2 people, by virtue of having been sharing personal space together for a bit, are now falling into a more natural level of conversational exchange. Just reading it, I imagine that the driver is older than the passenger, so is adopting a somewhat fatherly tone. However, the passenger is still the customer (higher status) so the customer doesn't need to speak formally even though the driver is an older person.

In sum... teaching です、ます in Japanese language classes is the right thing to do, because it's always OK to be polite. However, being able to switch appropriately and knowing when it's OK to do so, is probably something that only comes with time in Japan in a variety of social situations.

Good luck!

Answer 5

To throw a few things out there. I think textbooks do the です/ます more for verb recognition and conjugation flags than a specific emphasis on speaking polite (big blanket statement) and the concept of です/ます being polite and not using it being impolite is not a paradigm. 80% of your daily interactions in Japan are in standard Japanese (だ/る) so its of the utmost importance to internalize those patterns IMHO. To address your direct questions - Ending a sentences in particle or dropped verb - Normal and important. without that you would have to say a fully formed sentence. Consider this in daily life in English. aさん"When is the meeting?" bさん "at 2." here you are unlikely to reply with a full and proper "The meeting is at 2 o'clock" Japanese has the same liberties to shorten the sentence up.

• When to use です/ます and when not? It can take some time to learn to sense it but use it when

1- don't yet know the persons social status

2- if you are in service of the person(s). (where, the person just being older constitutes them as sharing their life experience with you, thus in their service)

• When not... ask yourself, would you be that persons friend? if yes, drop the です/ます