YOU SAID:

I saw sally selling seashells by the seashore.

INTO JAPANESE

海岸近くで貝殻を売っていたのを見ました。

BACK INTO ENGLISH

I saw that they were selling shells near the coast.

INTO JAPANESE

私は彼らが海岸近くで殻を売っているのを見ました。

BACK INTO ENGLISH

I saw them selling shells near the shore.

INTO JAPANESE

私は彼らが海岸近くで貝殻を売っているのを見ました。

BACK INTO ENGLISH

I saw them selling shells near the shore.