In short

English has one “and”; Japanese picks a different tool depending on what you are joining and whether the list is complete. Nouns: と to is the full list, や ya and とか toka are samples (“things like”). Clauses: し shi stacks reasons or qualities that all point the same way. Verbs: 〜たり〜たり + する gives a sample of activities. The one that trips everyone up is たり - it is a representative list, never a sequence of events.

The rule

Step 1 - Listing nouns: と is closed, や is open

と joins nouns into an exhaustive list: these and nothing else.

• 机の上に本とノートがあります。 (Tsukue no ue ni hon to nōto ga arimasu.) - a book and a notebook, that is the whole contents.

や joins nouns into a representative list: these, and other things besides.

• 机の上に本やノートがあります。 (Tsukue no ue ni hon ya nōto ga arimasu.) - a book, a notebook, and more.

In modern Japanese both normally go between the nouns, with nothing after the last one: 本やノートや -> ✗. (A final と does survive in formal or set phrases - 君とぼくとの仲 kimi to boku to no naka - but a dangling や is not used.) To make the open-endedness explicit, close the list with など nado (“and so on”): 本やノートなど hon ya nōto nado. や and など are a natural pair, and など may also follow a single noun.

Step 2 - とか: the spoken version of や

とか is the colloquial equivalent, with two freedoms や does not have.

1. It may follow the last item too: パンとか牛乳とか買ってきてください。 (Pan toka gyūnyū toka katte kite kudasai.)
2. It attaches to verbs and clauses, not just nouns: 休みの日は本を読むとか、映画を見るとかしています。 (Yasumi no hi wa hon o yomu toka, eiga o miru toka shite imasu.)

Register order, casual to formal: とか < や < や〜など. とか is everywhere in speech; in a report or a formal email use や〜など.

Step 3 - Listing clauses with し

し joins whole clauses that all point in the same direction - several reasons for one conclusion, or several good (or bad) points about one thing. It attaches to a plain predicate, or to a polite one like から does; after a noun or な-adjective you need だ (plain) or です (polite): 静かだし shizuka da shi, never ✗静かし.

• この店は安いし、おいしいし、店員も親切です。 (Kono mise wa yasui shi, oishii shi, ten’in mo shinsetsu desu.)

Notice も in the last clause. し-lists love も, because each item is one more piece of evidence piling onto the same verdict - “cheap, and tasty, and on top of that the staff are nice.”

A single し already implies “and there’s more”. 今日は疲れましたし、帰ります (Kyō wa tsukaremashita shi, kaerimasu) means “I’m tired, for one thing, so I’ll go home” - it hints at unstated further reasons, which is exactly what makes it feel softer than から.

Step 4 - From し to から: a softened reason

Because a し-clause offers a reason without insisting on it, it is a gentler way to explain yourself than から (lesson 21). Two common shapes:

• し alone, with the conclusion following: 雨だし、今日はやめましょう。 (Ame da shi, kyō wa yamemashō.)
• し-clauses stacked, then から／ので on the last one, which delivers the verdict: 安いし、近いから、この店にします。 (Yasui shi, chikai kara, kono mise ni shimasu.)

You can also stop after the し and let the listener finish the thought - もう遅いですし…… (Mō osoi desu shi……) is a complete, polite refusal.

Step 5 - Listing verbs: 〜たり〜たり + する

For activities, take the た-form of each verb, add り, and close the whole thing with する - which carries all the tense and politeness for the sentence.

V-た + り、V-た + り + します／しました

• 休みの日は本を読んだり、映画を見たりします。 (Yasumi no hi wa hon o yondari, eiga o mitari shimasu.)

Two verbs is the standard; one たり is also fine and means “…and things like that”. Adjectives and nouns join in too: 暑かったり寒かったり atsukattari samukattari, 雨だったり ame dattari.

A pair of opposites gives alternation - back and forth, on and off: 雨が降ったりやんだりしています。 (Ame ga futtari yandari shite imasu.)

And 〜たりして on its own is a hedge, floating a possibility without committing: もしかしたら、彼も来たりして。 (Moshikashitara, kare mo kitari shite.) - “Maybe he’ll even turn up.”

Step 6 - What たり does NOT mean

たり is not a sequence. It never means “I did A, then B”. Those two verbs are a sample of what happened, in no particular order. For real sequence use the て-form or てから (lesson 23):

• ✗ 朝ご飯を食べたり、学校へ行ったりします。 (as “I eat breakfast, then go to school”)
• ○ 朝ご飯を食べてから、学校へ行きます。 (Asagohan o tabete kara, gakkō e ikimasu.)

Forms & patterns

Joining nouns - four markers, one decision:

What し attaches to (same pattern as から - plain or polite, but a noun/な-adjective needs the copula):

Building 〜たり - it is the た-form plus り, so the た-form rules do all the work (lesson 17):

Examples

Common mistakes

• 映画を見るや本を読みます。 (Eiga o miru ya hon o yomimasu.) -> 映画を見たり本を読んだりします。 (Eiga o mitari hon o yondari shimasu.) - や joins nouns only. For activities use 〜たり〜たり, or the colloquial 〜とか〜とか.
• 本を読んだり、映画を見ます。 (Hon o yondari, eiga o mimasu.) -> 本を読んだり、映画を見たりします。 (Hon o yondari, eiga o mitari shimasu.) - every listed verb takes り, and the list must be closed by する. Leaving the last verb bare breaks the pattern.
• 昨日は本を読んだり、音楽を聞いたりします。 (Kinō wa hon o yondari, ongaku o kiitari shimasu.) -> ……聞いたりしました。 (…kiitari shimashita.) - たり itself has no tense. All tense sits on the final する, so a past sentence needs しました.
• この部屋は静かし、便利です。 (Kono heya wa shizuka shi, benri desu.) -> この部屋は静かだし、便利です。 (Kono heya wa shizuka da shi, benri desu.) - a な-adjective or noun needs the copula before し: 静かだし／静かですし. An い-adjective attaches directly: 安いし.
• 毎朝、起きたり、顔を洗ったりします。 (Maiasa, okitari, kao o arattari shimasu.) -> 毎朝、起きてから、顔を洗います。 (Maiasa, okite kara, kao o araimasu.) - たり lists a random sample, so it cannot express “first this, then that”. Sequence is the job of て／てから.

Tips

• Sort by what you are joining. Nouns -> と／や／とか. Whole clauses (reasons, qualities) -> し. Activities -> 〜たり〜たり + する. Get that first choice right and the rest is mechanical.
• と says “that’s the lot”. Answering 何を買いましたか with パンと牛乳を買いました claims you bought exactly two things; パンや牛乳を買いました leaves room for the rest of the basket. When you are not sure a list is complete - which is most of the time - や or とか is the safer, more natural choice.
• し is not a neutral “and”. It always argues for something. Stringing neutral facts together with し sounds like you are building a case, so for plain sequential description use the て-form instead.
• The closer carries everything. In a たり sentence, politeness, tense and negation all live on the final する: しています, しました, しません. Learners often try to conjugate the たり itself - there is nothing there to conjugate.