整理 E 「〜わけ」のいろいろな使い方 教科書 p.74
Ways to use 〜わけ
接続：普通形 + わけだ
no wonder / that means…. State a natural conclusion after knowing the cause or chaining together previous information.
注意 / Note：Check the correct front form, subject and level of politeness; Don't just translate word for word.
比較 / Compare：Compare with structures in the same lesson to choose according to function in the whole sentence. Same 課: 〜わけにはいかない／〜など／〜なんか — these models are often mistaken for each other, read the 接続 line carefully and then decide.
十年日本にいたのですか。日本語が上手なわけですね。
You've been in Japan for 10 years, no wonder you're good at Japanese.
今日は祝日です。銀行が閉まっているわけだ。
Today is a holiday, no wonder the banks are closed.
サーバーは点検中だったんですか。アプリにつながらないわけですね。
Is the server under maintenance? No wonder the app can't connect.