Even though I’m still a beginner, maybe I should chip in with some advice here and there too.
Thanks for the warning! I’ll be careful!
黒い is an い-adjective. When using an い-adjective to describe a noun (金曜日), it can’t be followed by な. な is only used for な-adjectives. For more reading, see:
(Aside from that, I’m not sure if 黒い金曜日 would really be understood as “Black Friday”. I think you’d usually say ブラックフライデー. Though I do like how your sentence gives maximum translation practice that way.)
Great effort! Your usage of AがあるB is slightly incorrect though.
The grammar pattern AがあるB used in this sentence only serves as a relative clause. The main clause (家) would still need some kind of verb to make sense. Literally, your sentence would mean something like:
The house that has my room. (What information do you want to present about the house?) This room is spacious.
So, in this case, you don’t need a relative clause to express this idea, so the Japanese would be something like:
(この)家には僕の部屋がある。この部屋はとても広い。
If you want to use the がある grammar point in this sentence you could do something like this:
The house that has my room has 10 people.
僕の部屋がある家には、10人がいる。
Here, the grammar point works since you still express your “main idea” in the main clause.
Also, the sentence 僕に正すお願いします is slightly off:
正す is a transitive verb, so it takes a direct object, meaning:
僕を正す is the correct form. https://guidetojapanese.org/learn/grammar/in-transitive
Also, お願いします can only be used with nouns, so you’d either need to nominalize it with こと or の
As in:
僕を正すのをお願いします。
僕を正すことをお願いします。
But a more natural way to express “Please do X.” is て + 下さい, as in:
Tomorrow I’m going to a Thanksgiving party with my friends. Everyone is bringing different side dishes, but, because I don’t have an oven, it’s difficult to make Western food. In the worst case that I can’t make anything, I will buy a Japanese style dish!
When going to the toilet, I mustn’t forget to lower my trousers.
Man, it sure takes me a while to produce these sentences. I have to think a lot while trying to make sentences with these grammar points. Gotta practice a lot to make it come more naturally!
And for good measure: たり~たりする (JLPT N5) | Bunpro
トイレにいた時に、すどくをしたり、YouTubeどうがを見たりしました。
(I do realise “時” isn’t the most suitable word for this situation, but I haven’t learned the right vocab for this yet.)
English
While I was on the toilet, I did things like sudoku puzzles and watching YouTube videos.