I need help to understand this sentence: おじいさんはないをやらせてもだめなんだもの

Question

I'm a totally newbie in learning Japanese and I'm struggling to understand that sentence:

おじいさんはないをやらせてもだめなんだもの。

I know おじいさん is "grandfather" and it seems like はない means "is not present", but if so I don't understand the role of the particle を.

The following part is quite dark to me: maybe だもの could indicate a reason, but I'm not sure about it.

Thank you.

な**い**をやらせても <- You sure you've copied it correctly? It should be な**に**をやらせても. — Chocolate, Aug 11 '20 at 13:33
Welcome to JLSE. You've shown your research effort, so I voted to reopen this question. Meanwhile, as Chocolated pointed out, this ないを is clearly a typo for なにを. Does this help you understand the sentence more? — naruto, Aug 11 '20 at 14:01

score 13 · Accepted Answer · answered Aug 11 '20 at 14:17

This ない is clearly a typo for なに.

おじいさんはなにをやらせてもだめなんだもの。

Grandpa is no-good whatever we have him to do.

I can't get my grandpa to do anything!

おじいさんは: You got this part right. "as for Grandpa"
なにをやらせても: やらせる is the causative-form of やる, or "make/let him do". を simply marks the object of やる. "何/どこ/誰 + ても" is a grammar pattern that means "whatever" etc. See: Meaning of volitional passive form / Maggie Sensei: Wh-ever/No matter wh/how: ても/でも ( = temo/demo)
だめなんだ: だめ means "no good", "useless", etc.
もの: もの is a little old-fashioned sentence-end particle used to present a reason and convince someone. See: 〜ものだから　〜もの　～もん What are the differences? / JLPT N2 Grammar もの/もん

Thank you, your explanation is very clear! – Fede Aug 11 '20 at 22:20 — Fede, Aug 11 '20 at 22:20

1 Answers1