[Serie: All About Japanese Particles]
1. Indicates an absolute quantitative limit with the connotation that the amount is small: “only, just.”
昨日クラスに来た学生は、5人だけでした。
Kinō kurasu ni kita gakusei wa, gonin dake deshita.
Only five students came to class yesterday.
今日は1時間だけテレビを見ました。
Kyō wa ichi-jikan dake terebi o mimashita.
Today I watched TV for only an hour.
2. Indicates an extent or amount: “as … as.”
どうぞお好きなだけお飲みください。
Dōzo osuki na dake onomi kudasai.
Please drink as much as you wish.
できるだけ早く行きます。
Dekiru dake hayaku ikimasu.
I’ll go [be on my way, leave, get there] as soon as I can. (Lit., To the extent that I can, I will go quickly.)
*3. In the phrases dake ni, dake atte, and dake no koto wa aru, indicates the cause or precondition for a certain result or state of affairs (when the result meets expectations, does not meet expectations, or is considered a natural outcome).
a) When the result meets expectations and is therefore worth the effort of achieving: “… was worthwhile.”
あの大学に合格できたから、勉強しただけのことはあった。
Ano daikagu ni gōkaku dekita kara, benkyō shita dake no koto wa atta.
I passed [the entrance examination to] that university, so the studying I did was worth it.
寺田だんは私のプレゼントを喜んでくれたので、無理して買っただけのことはあった。
Terada-san wa watashi no purezento o yorokonde kureta no de, muri shite katta dake no koto wa atta.
Since Terada was happy [pleased] with my present, it was worth all the trouble I went to in buying it.
b) When the result does not meet expectations and is therefore discouraging: “given the fact that.”
彼は彼女に夢中だっただけに、失恋のショックはとても大きかった。
Kare wa kanojo ni muchū datta dake ni, shitsuren no shokku wa totemo ōkikatta.
Given the fact that he was head over heels in love, losing her was a big blow.
一生懸命に勉強しただけに、不合格の通知を受け取ったとき、山本さんは非常にがっかりした。
Isshō-kenmei ni benkyō shita dake ni, fu-gōkaku no tsūchi o uke-totta toki, Yamamoto-san wa hijō ni gakkari shita.
Since he had studied so hard, Yamamoto was extremely disappointed when he received notification that he had failed. / Given the fact that he had studied so hard, Yamamoto was crushed when he learned that he had not been accepted.
c) When the outcome is seen as a natural result of foregoing conditions: “as you might expect.”
佐藤さんは英国の大学で勉強しただけあって、英語がうまいですね。
Satō-san wa Eikoku no daigaku de benkyō shita dake atte, Eigo ga umai desu ne.
As you might expect from his having studied at a university in England, Sato’s English is quite good.
ジョンさんは、京都に15年も住んでいるだけあって、お寺のことをよく知っています。
Jon-san wa, Kyōto ni jūgo-nen mo sunde iru dake atte, otera no koto o yoku shitte imasu.
As you might expect from his having lived in Kyoto for fifteen years, John is very knowledgeable about temples. / Since John has lived in Kyoto for fifteen years, it is not surprising that he knows a lot about temples.
一流のピアニストだけに、すばらしい演奏をしますね。
Ichiryū no pianisuto dake ni, subarashii ensō shimasu ne.
As you might expect of a first-rate pianist, he plays wonderfully, doesn’t he.
ここは北海道だけに、寒さが厳しいです。
Koko wa Hokkaido dake ni, samusa ga kibishii desu.
As you might expect from this being Hokkaido, it is terribly cold. / It is terribly cold here in Hokkaido, as you might expect.
Note: While bakari (#21, no. 2) may replace dake in this usage, it is slightly more emphatic.
原田さんはピアノだけでなく、歌もうまいんですよ。
Harada-san wa piano dake de naku, uta mo umai-n desu yo.
Harada is good not only at the piano but also at singing.
英語だけでなくフランス語も勉強したいんです。
Eigo dake de naku Furansu-go mo benkyō shitai-n desu.
I want to study not only English but French as well.
– Source: All about particles – A handbook of Japanese function words –
