Forgive me if I go too in depth on matters you are already familiar with, but just in case you aren’t or if anyone else reads: Currently, I see よく used 2 ways most often. Yeah, there are a lot of different ways it can be used, but this is what I’ve noticed in my low-level ability so far. It usually means either “often” or “well”.
いい = good, right?
よい is the older version of いい, which we have to use if we want to conjugate it to any other forms.
In order to turn an い adjective into an adverb, we change the い to く
よい → よく
so いい/よい = good
よく = well / often
However, directly translating a lot of Japanese stuff is going to get you in trouble, so you have to try to take the feeling of よく and apply it to whatever it’s modifying. Basically just saying whatever it’s modifying is being done well or often.
見える can see
よく見える can see well
運転する to drive
よく運転する drive well / drive often
似てる to look like/to look alike
よく似てる to look alike (more than usual / a lot / well)
As Naphthalene said, の in this case is a nominalizer.
Take this English exchange for example:
A: Whose umbrella is this?
B: It’s my umbrella.
B probably wouldn’t say umbrella again, right? They would just say, “It’s mine.”
In Japanese, it would go more or less the same way.
A: 誰の傘ですか?
B: 私のです
Note that B doesn’t say 私の傘. We already know what’s being talked about, so we don’t have to say the noun again. I think knowing this step is important to knowing how the の in the sentence you asked about works. Usually, こと would be at the end of the phrase you asked about:
日本へ来ることは
This is super duper common in Japanese, so as a shortcut, we nominalize the こと to の since everyone knows how the grammar works, so it becomes 日本へ来るのは
Also, you can add 目 onto a counter word to talk about a specific one in the list.
3匹の犬 3 dogs
3匹目の犬 third dog
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