Wow, nice job, dude! I see that you are indeed learning Latin like you say. ;P
Yeah, I'm not surprised that those would be weird sentences because they were just part of a Linguistics exercise. However, if I remember correctly from my study of Spanish in high school, then I may have a suggestion to make the translations a little less weird.
I remember hardly any Spanish, but I think this is correct: La casa del hombre. The literal translation of that would be, "The house of the man," but a more natural translation in English would be, "The man's house." If this slight change of wording is applicable to translations from Latin, then maybe those sentences would sound a little better with it applied.
The above suggestion does not apply to Japanese, so I may have no idea what I'm talking about anymore.