ばかり

The word ばかり has a variety of uses, and one of them is to express the idea that someone does one thing all the time, and does nothing but that particular activity. For example, "Alex does nothing but play soccer."

Its placement depends on the type of sentence. With a noun + verb construct, it can replace the particle there (such as を). With する verbs, the pattern would be the verbal noun + ばかり + する. It can also be placed directly after the て form of a verb (before the いる) to express something ongoing.

弟は肉ばかり食べて、野菜や果物は全然食べようとしません。
My little brother eats nothing but meat, and he never tries to eat fruits or vegetables.

リーさんは日々部屋でテレビばかり見て、悩み始めてるんだけど。
Lee-san does nothing but watch TV in his room day after day, and I'm beginning to worry.

赤ちゃんが泣いてばかりいるので、母親になったばかりの洋子さんはとても困っている。
Since the baby does nothing but cry, Youko-san, who just became a mother, is very troubled.

毎日勉強ばかりしたいけど、お母さんは外でもっと遊ぶの方がいいってんだな。
I want to do nothing but study every day, but my mom says I should play outside more.