to begin to drink
薬を飲み始めたら体調が改善した。
Once I started taking the medicine, my condition improved.
朝からコーヒーを飲み始めているせいか眠れない。
Maybe because I've been drinking coffee since morning, I can't sleep.
医師に勧められてサプリを飲み始める予定だ。
I plan to start taking supplements as recommended by my doctor.