Tsutsu and Tsutsu Aru in Japanese: While, Although and In Progress

How to form tsutsu

Tsutsu attaches to the masu stem of a verb, the part before masu: nomi from nomimasu, tabe from tabemasu, shi from shimasu. It does not attach to nouns or adjectives, and it cannot take a negative directly.

The three uses share the same stem. Add mo for although, and add aru, or arimasu in polite form, for a change in progress. In writing, tsutsu aru often appears as tsutsu ari, followed by a comma, in long sentences.

Tsutsu as while: the formal nagara

In its basic use, tsutsu joins two actions done by the same subject at the same time. The main action comes second; the tsutsu action is the background. Kawa o nagametsutsu, sanpo shita means I took a walk while gazing at the river.

The meaning is the same as nagara, but the register is higher. You will see tsutsu in essays, formal letters, speeches and business documents, especially with verbs of thinking and considering, such as kangaeru, omou and kentō suru.

A common formal use is combining an action with a wish or feeling in closing lines. Minasama no go-kenkō o inoritsutsu means while praying for your good health, and it appears at the end of letters and speeches.

Tsutsu mo: although, even while

Adding mo turns tsutsu into a concessive: although, even though or while at the same time. The first part states what the person knows, thinks or feels, and the second part describes an action that goes against it. Plain tsutsu can carry this meaning too, especially with shiru and omou, but mo makes it clear.

The most common combinations are to shiritsutsu mo, while knowing that, and to omoitsutsu mo, while thinking that. They often describe regret or giving in to temptation, and they are useful in reflective writing and in apologies.

The last example is a standard apology in emails: it admits you knew you should have replied and gives the reader a sense of sincere regret. Follow it with mōshiwake gozaimasen.

Tsutsu aru: a change in progress

Tsutsu aru describes something moving gradually towards a new state: is increasing, is recovering, is disappearing. It is typical of news reports, business analysis and academic writing, where trends matter.

It works best with verbs of change, such as fueru, to increase, heru, to decrease, kawaru, to change, kaifuku suru, to recover, and hatten suru, to develop. The sense is that the change has started but is not yet complete.

Tsutsu aru is less natural with verbs that describe an ongoing activity with no endpoint, like taberu or hashiru. For those, te iru is the normal choice.

Tsutsu vs nagara

Both patterns attach to the masu stem, and both have a while and an although meaning. The differences are register and range. Nagara works in any context, from casual chat to writing. Tsutsu is formal and mostly written.

Nagara also extends beyond verbs in its although meaning: zannen nagara, unfortunately, semai nagara mo, small though it is, and kodomo nagara, though only a child. Tsutsu never does this; it only follows verbs.

Tsutsu aru vs te iru

Te iru has several meanings: an ongoing action, a resulting state or a habit. With change verbs, it often describes the result: shinde iru means is dead, kekkon shite iru means is married, fuete iru can mean has increased. Tsutsu aru isolates the process: the change is under way and still moving.

That makes tsutsu aru useful when you want to be precise about a trend. Jinkō ga hette iru can mean the population has fallen or is falling; jinkō ga heritsutsu aru clearly means the population is in the process of falling.

Common mistakes with tsutsu

• Using different subjects: watashi ga benkyō shitsutsu, haha ga ryōri shita is wrong. Like nagara, tsutsu needs the same subject for both actions; use aida ni for different subjects.
• Attaching tsutsu to adjectives or nouns: semaitsutsu is wrong; use semai nagara mo.
• Using tsutsu aru with activity verbs: tabetsutsu aru sounds odd for I am eating. Use tabete iru.
• Using tsutsu aru with stative verbs: itsutsu aru and aritsutsu aru are not used; state verbs do not change.
• Using tsutsu in casual chat: terebi o mitsutsu gohan o tabeta sounds stiff between friends. Say terebi o minagara.
• Forgetting the masu stem with suru verbs: write kentō shitsutsu, not kentō suru tsutsu.

Where you will meet tsutsu

Tsutsu is a reading and listening skill first. You will meet it in news about the economy and society, in company reports and press releases, in formal letters and in speeches at ceremonies. Recognising the three uses quickly makes these texts much easier to follow.

For speaking, a few chunks are worth making your own: to shiritsutsu mo for admitting a weakness, to omoitsutsu for apologising for a delay, and tsutsu aru when presenting trends in a meeting. Used in the right place, they make your formal Japanese sound polished.