English studying: Preposition

I always get confused with preposition in English such as at, by, and until. I had a chance to review them during work today. I was translating a document and had to think of the due date. I especially got confused with by and until.

Please refer to the online dictionary below for the meanings. It's interesting to know that explanation is different from the  different dictionaries.

Example of a sentence using by

I need to finish homework by tomorrow.

Example of a sentence using until

There is a meeting from 11 am until noon.

It's difficult to explain the difference in words. I think until has the meaning of continuous period. Even now, I'm not sure if I really understood the differences. When I translate Japanese to English, I keep thinking of the original Japanese sentence. Therefore, my English sentence become strange and it doesn't sound natural.

It's necessary for me to review the grammar once in a while or whenever I feel something is wrong. I also review with the grammar book below. I should be reviewing the preposition column again.

表現のための実践ロイヤル英文法

Longman Dictionary

by | ロングマン現代英英辞典でのbyの意味 | LDOCE (ldoceonline.com)

until | ロングマン現代英英辞典でのuntilの意味 | LDOCE (ldoceonline.com)

Oxford Dictionary

by_1 preposition - Definition, pictures, pronunciation and usage notes | Oxford Advanced Learner's Dictionary at OxfordLearnersDictionaries.com

Cambridge Dictionary

BY | English meaning - Cambridge Dictionary