"My mother washes vegetables."
Translation:우리 어머니께서 야채를 씻으신다.
Very few Koreans refer to their mother as 어머니께서. The DL course would be far more effective to limit the range of answers with a hint or a scenario to give context and the politeness expected in the response. Hopefully, by the time it comes out of beta some of the inconsistencies will have been removed.
My guess is that if you asked 100 Korean Hitgh school students to translate this sentence into English, an overwhelming majority would use "엄마는 야채를 씻어. "는" would be used to contrast the action of the student, who probably wouldn't bother to wash them.
For Renee, in this situation the "ㄴ" is not related to past tense as when a verb has been changed to an adjective. It is simply an element of 해라체 (written / text form) For an active verb, the "ㄴ" is inserted before "다", but omitted in a descriptive verb.
For yoongihante, the braces are worth it. I'm reminded of the old tongue twister "Sheila sells sea shells down by the sea shore."
There is no such thing as "셔요". Honorific particle 시 is always changed into 세 when 요 is right behind it.
씻으셔요 is wrong. 씻으세요 is the way to go.
EDIT: well, 셔요 is not wrong, I was confused when writing that. It might be unnatural in modern times, but there's nothing incorrect about that.