Listing and repeating actions with 〜たり〜たり and ては

We already saw in Lesson 36 it is possible to make non-exhaustive lists of verbs using the listing particle とか.

たり is another particle/conjugation that can be used in a similar way. It is actually more common and conversational to use it like this over とか.

The たり form of a verb is simply the past tense + り:

At the end of a list of 〜たり actions, it is natural to attach the verb する which turns the entire block of verbs into a conjugable phrase that behaves like a giant verb.

手をつないだり、抱きしめあったり、キスをしたりしたいから。
Because I want to do things like holding hands, embracing each other, and kissing.

Unlike chaining verbs using て form, たり does not assume any strict ordering or precedence of action. It simply states that any of those actions (and even other unstated ones) takes place in whatever order. AてB roughly means "Do A, then do B", while AたりBたりする means "do things like A and B".

Aside its most basic explanation, it has a few other specific idiomatic uses. It can be used to:

• soften a statement;
• add the nuance that what you're saying is meant to be surprising for the listener;
• state a common occurrence;
• state a likely possibility.

These idiomatic uses of たり sometimes overlap so it's not easy to pinpoint exactly which usage is which.

Just like other non-exhaustive listing particles, it can work with just a single element in the list.

笑ったりしてごめんなさい。
I'm sorry for laughing. 

実はそうだったりする
In fact, that's actually the case.

昔はよく一緒に遊んだりしました.
We used to play together a lot in the past.

もしかしてお金が必要だったりするのだろうか？
Is it the case that you might be needing some money maybe?

〜たり〜たり can also be used to highlight two actions that happen repeatedly in alternation. In this usage, the two actions are often natural opposites, and the する verb is not used at the end of this たり group.

大きくなったり小さくなったり。
It grew big, and then small, and then big, and then small...

The ては conjugation can also be used in a similar manner.

飲んでは笑い、笑っては飲む。
He drinks and laughs, then laughs and drinks.