だけは is another one of the many grammar patterns in Japanese that includes the particle だけ, meaning ‘just’ or ‘only’. In this particular structure, だけ pairs with は, and presents a specific verb as the topic to indicate that it is being done ‘as much as one can’. The same verb will be repeated both before and after
だけは, with the one coming second usually appearing in its past-tense or ている form.
Imagining that the target verb was 食（た）べる ‘to eat’, the literal translation of something like 食（た）べる
だけは食（た）べた would be ‘I ate just what I could eat’. Because this pattern frequently discusses possibilities, it is also very common for the first verb to be in the potential れる or られる form.
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飲（の）み放題（ほうだい）だったから、飲（の）めるだけは飲（の）んだ。
It was all you could drink, so I drank as much as I could.
トイレットペーパーを買（か）えるだけは買（か）ったが、置（お）く場所（ばしょ）がない。
I bought as much toilet paper as I could afford, but I have nowhere to put it.
ピアノのレッスンには通（かよ）うだけは通（かよ）っているけど、ピアノにはあまり興味（きょうみ）がない。
I go to piano lessons as much as I can, but I am not very interested in piano.
毎日（まいにち）漢字（かんじ）の勉強（べんきょう）をするだけはしているが、上達（じょうたつ）している感（かん）じがしない。
I do as much as I can to study kanji every day, but I don't feel like I'm making progress.
Caution - It is also relatively common to see する omitted following the first verb, and only being used after
だけは. In this kind of pattern, the target verb itself will not usually be repeated after
だけは.
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勉強（べんきょう）だけはしたが、全然（ぜんぜん）頭（あたま）に情報（じょうほう）が入（はい）ってこなかった。
I studied as much as I could, but I didn't get any information in my head.
先輩（せんぱい）には何回（なんかい）も連絡（れんらく）だけはしているが、全然（ぜんぜん）返事（へんじ）をしてくれない。
I have been trying to contact my senpai as much as I could, but he won’t respond at all.