Do I use "する時" or "ている時" when talking about something in general?


When something is happening and another thing also happens or is happening in
general in English, we can use Verb+ing form after "when" or "whenever" to
express the idea, like the two examples below.

**Example 1:**

> When/Whenever I **am watching TV** , my friend annoys me.

**Example 2:**

> When/Whenever I am **doing my homework** , my younger brother is playing
> video games.

* * *

**Question:**

If I want to express the same concept in Japanese, do I use "する時" or "ている時"?

> When/Whenever I am watching TV, my friend annoys me.
>
> **Example 3:** 私がテレビを **見ている** 時、友達が邪魔する。
>
> **Example 4:** 私がテレビを **見る** 時、友達が邪魔する。

> When/Whenever I am doing my homework, my younger brother is playing video
> games.
>
> **Example 5:** 私が宿題を **している** とき、弟はゲームをやっている。
>
> **Example 6:** 私が宿題を **する** とき、弟はゲームをやっている。




I want to expand a bit on [this question's
answer](https://japanese.stackexchange.com/questions/61401/difference-
between-%e3%81%9f-%e3%81%a6%e3%81%84%e3%82%8b-plain-form-%e3%81%a8%e3%81%8d),
which is very similar.

Example 3 is good. It means that when you are watching TV, your friend annoys
you.

Example 4 means "right before I watch TV, my friend annoys me" (which is
pretty nonsensical...)

Example 5 and 6 have a similar problem. Example 6 means "right before I do my
homework, my brother plays games".

In general, if you are in a state when something else happens, use ている to
specify that it is indeed a state. Otherwise, if the verb is an action, the
meaning changes.

Edit: in response to the comment by a20, I've cited a source for my
translations, A Dictionary of Basic Japanese Grammar, page 493:

[![DBJG, p
493](https://i.stack.imgur.com/lEeWV.png)](https://i.stack.imgur.com/lEeWV.png)




Examples #3 and #5 sound natural for what you mean.

Example #4 is also fine if you are talking about what habitually happens, as
opposed to a specific instance in which you are already watching TV and your
friend disturbs you. I think you can say “When/Whenever I **watch** TV” in
English for this sense, too.

While example #6 could also be understood as referring to a habit, it sounds a
bit odd because of the progressive やっている. It sounds as if your brother is
already in the middle of playing a game by the time you sit down to do your
homework, and that happens every time you do so.

