Imagine that I thought of a clever way to start this lesson.

I told a funny story about my once exciting life in Tokyo, including some embarrassing mistakes I made, some lifelong friendships I established, and a delicious piece of sushi or two.

Then BAM! Mega-smooth transition into today's lesson topic:

JLPT N3: ついでに (while; when; at the same time; incidentally)

We use ついでに when one event or action (A) makes it convenient to also complete a second action (B).

Consider the following example:

髪を切るついでにカラーリングとトリートメントもしようかな。
かみ　を　きる　ついでに　カラーリング　と　トリートメント　も　しよう　かな。
When I get my hair cut, maybe I’ll also get coloring and a treatment.
Literally: “hair + を + cut + ついでに + coloring + と + treatment + も + let’s do + かな.”

In this example, the action/event for "A" is getting a haircut. And the convenient action to accomplish alongside it is "B," getting coloring and hair treatment.

There is no perfect English for ついでに, but the closest equivalents we have are probably "while," "at the same time," "incidentally," "when," etc.

All you need to remember is the following:

An original, planned action (e.g. "get a haircut") goes before ついでに, and an additional, opportunistic action (e.g. "get coloring and a treatment") goes after ついでに.

👷 Construction👷

Since the thing coming before ついでに must be an action, the word coming before ついでに must be a VERB or something else that expresses action (namely, a するNOUN [=a noun that can be followed by する]).

Specifically, we can form phrases this way:

V る ＋ ついでに

V た ＋ ついでに

するNOUN ＋ の ＋ ついでに

Here's an example of each of these formations:

切るついでに
きる　ついでに
while cutting; when cutting; at the same time as cutting
Literally: "cut + ついでに"

作ったついでに
つくった　ついでに
while making; when making; at the same time as making
Literally: “made + ついでに”

引っ越しのついでに
ひっこし　の　ついでに
while moving; when moving; at the same time as moving
Literally: “moving (residence) + の + ついでに”

Now, the big question any time we study JLPT grammar: Is this used in everyday life?

Yes!

I use it all the time, and I hear it being used quite a bit, too. So even if you're not taking JLPT tests, studying this is certainly worth your while (as is typically the case for all N5, N4, and N3 grammar; we don't get too much obscure grammatical language until N2 and N1).

引っ越しのついでにいろんな家具を買い替えた。
ひっこし　の　ついでに　いろんな　かぐ　を　かいかえた。
I replaced a lot of my furniture when I moved.
Literally: “moving + の + ついでに + various + furniture + を + bought replacements for.”

In this example, moving was an original, planned action. This presented a good opportunity to add the second action of buying new furniture at the same time.

You may be wondering how we can have a past tense verb (V た) coming before ついでに.

Although the use of past tense in grammatical formations can sometimes be tricky (e.g. using the past tense when talking about things we're still doing or will be doing), ついでに is not so complicated. We can simply use a past tense verb before ついでに any time we're talking about two actions that were done in the past:

夕食を作ったついでに、お弁当用のおかずをたくさん作って冷凍した。
ゆうしょく　を　つくった　ついでに、　おべんとう　よう　の　おかず　を　たくさん　つくって　れいとう　した。
While I was making dinner, I also made a lot of side dishes to freeze for bento.
Literally: “dinner + を + made + ついでに, + bento + -use + の + side dishes + を + many + made (and) + freezing + did.”

When I am using a Japanese word in English, such as "bento," I never know how to put it in the plural form. Bento? Bentos? Benteese? ^_^

By the way, have you ever noticed how Japanese meals tend to consist of so many little bowls, plates, and other dishes? This is largely thanks to the great variety of おかず or "side dishes" that appear in Japanese cuisine. They are delicious, and a great way to add some much-needed greens to a meal.

Last of all, we have a somewhat special example:

A:
ちょっとコンビニ行ってくる。
ちょっと　コンビニ　いって　くる。
I’m gonna run to the convenient store.
Literally: “little + convenience store + go (and) + come.”

B:
じゃあついでにタバコ買ってきて。
じゃあ　ついでに　タバコ　かって　きて。
While you’re there, get me some cigarettes.
Literally: “then / well + ついでに + tobacco + buy (and) + come.”

As you can see here, it is possible to start a sentence with ついでに if it's clear that it is connecting to the action expressed in the previous sentence. Here it is clear that Person B is talking about "while going to the store," so there is no need to repeat 行ってくる in her sentence.

Person B's sentence is very useful if you ever want to ask a friend, roommate, or coworker to pick you up something when they run to the conbini! If I were saying it, I'd probably add くれない？ to the end of the sentence, which would make it a little less direct of a request (though still an informal request):

じゃあついでに [something] 買ってきてくれない？
じゃあ　ついでに　something　かって　きて　くれない？
While you’re there, will you get me [something]?
Literally: “then / well + ついでに +[something] + buy (and) + come + won't you give (me)?"

A nice phrase to add to your Japanese tool belt, if I may say so.