YOU SAID:

I accidentally knocked a hand against it and realized that it was made out of some kind of plaster, and it was hollow.

INTO JAPANESE

うっかり手をぶつけてしまい、それが石膏のようなものでできており、空洞であることに気づきました。

BACK INTO ENGLISH

I accidentally hit my hand on it and realized it was made of something like plaster and was hollow.

INTO JAPANESE

うっかり手をぶつけてみると、石膏のようなもので空洞になっていることが分かりました。

BACK INTO ENGLISH

When I accidentally hit it with my hand, I discovered that it was hollow and made of something like plaster.

INTO JAPANESE

うっかり手で叩いてみると、中は空洞で石膏のようなものでできていました。

BACK INTO ENGLISH

When I accidentally hit it with my hand, I found that the inside was hollow and made of something like plaster.

INTO JAPANESE

思わず手で叩いてみると、中は空洞で石膏のようなものでできていました。

BACK INTO ENGLISH

When I tried hitting it with my hand, I found that the inside was hollow and made of something like plaster.

INTO JAPANESE

手で叩いてみると中は空洞で石膏のようなものでできていました。

BACK INTO ENGLISH

When I pounded it with my hand, I found that it was hollow inside and made of something like plaster.

INTO JAPANESE

手で叩いてみると中は空洞で石膏のようなものでできていました。

BACK INTO ENGLISH

When I pounded it with my hand, I found that it was hollow inside and made of something like plaster.