”ばっか”, ”ばっかり” and ”ばっかし” are colloquial expressions for ”ばかり”.
They are adverbial particles that mean “only/nothing but”.
They are used to show that there is a single one, such as a certain group of people, a certain thing and a certain activity. They often indicate your surprise, shock and complaint.
Ken and Leo have been working overtime for the past four days.
- Ken: I have been busy all week and it doesn’t look like we’ll be finished anytime soon.
今週は仕事ばっかりだ。それに、(今日も仕事が)終わりそうにないね。 - Leo: It won’t take that long, but we don’t have time to talk. We’d better get back to work.
そんな時間はかからないけど、喋っている時間はないね。仕事に戻らなきゃ。 - Ken: Hmm, why does our boss always give us the kind of task that everyone hates doing? He is strict only with us, right?
んー、なんで(俺達の上司は)皆が嫌がる仕事を、俺達ばかりに振るんだ？俺達ばっかりに厳しいよね？ - Leo: You do nothing but complain!
文句ばっか！ - Ken: Sorry, I didn't mean it.
ごめん、そんなつもりはなかったんだけど。
Meg and her sister are watching TV while eating potato chips.
- Meg: They have been covering the same news all day! Is it okay if I change the channel?
一日中、同じニュースばっかりし！チャンネル(を)変えてもいい？ - Kumi: Sure. Do you want some?
いいよ。(チップス)いる？ - Meg: No, thank you. I’ll gain weight if I only eat snacks.
ううん、いいや。お菓子ばかり食べたら、太るもん。 - Kumi: You can eat as much as you like. You just need to work out later.
好きなだけ食べても、運動すればいいんだよ。 - Meg: It has been raining a lot lately. I can’t get enough exercise at home.
最近雨ばっかじゃん。家じゃ、ろくに(*)動けないよ。