「以前は〜だった」というのは
used to 〜（動詞の原形）
と表します。
その否定形で「以前はそれを好きではなかった」
I didn't use to like it
を使います。
it（それ）ではなく具体的にchocolate （チョコレート）で例を出してみます(o^^o)
「昔はそうでもなかったけど、今はチョコレートがすごく好き」なら
I didn't use to like chocolate but now I love it.
と言えます。
Chocolate の部分をスポーツの名前などに置き換えても使えます。
参考になれば幸いです。
I wasn't so interested before, but now I really like it.
I didn't really like it in the the past, but now I love it.
「昔は」は「以前は」というニュアンスで、 before や in the past また previously を使えばOK。
「そうでもない」は「あまり好きではない」という意味なので、not really like と言ってもよいですが、be not so interested を使うこともできます。 食べ物に関してだと好みがはっきりするので後者、スポーツや趣味に関わることならば、前者を使うと自然です。
I wasn't sold on the idea before but now I am hooked.
I wasn't particularly keen on it but now I love it.
I didn't really care much about it but now I love it
I wasn't sold on the idea before but now I am hooked.
Not sold on the idea = you didn't really care much about it /you were not really interested in it
I am hooked = when you are hooked on something it means it has your full attention and you love it.Just like going fishing and using a hook to catch fish and make sure that they don't let go/cannot escape.
I wasn't particularly keen on it but now I love it.
keen on it = interested in it
I didn't really care much about it but now I love it
care much about it = to not be interested in something
I wasn't sold on the idea before but now I am hooked.
Not sold on the idea = you didn't really care much about it /you were not really interested in it
I am hooked = when you are hooked on something it means it has your full attention and you love it.Just like going fishing and using a hook to catch fish and make sure that they don't let go/cannot escape.
「前は、そのアイデアに賛同しなかったけど、今はすごくいいと思う。」
Not sold on＝あまり関心がないこと。興味がないこと。I am hooked＝何かに夢中になること、はまること。Hookは魚の釣り針のことで、一度釣った魚が逃げないようにするイメージ。
I wasn't particularly keen on it but now I love it.
keen on it = interested in it
「特に興味はなかったけど、今はすごく好き。」
Keen on it＝興味がある。
I didn't really care much about it but now I love it
care much about it = to not be interested in something
「あまり興味なかったけど、今はすごく好き。」Care much about ＝何かに興味がないこと。
To be keen on something means that you enjoy/like it so if you were not so keen you did not really like it much
You could simply say "i wasn't too keen on it before bit now i love it"
「be keen on something」は、それ（something）が好きなことを表します。ですから「not too keen」は、あまり好きでないという意味になります。
シンプルに、以下のように言えるでしょう。
I wasn't too keen on it before but now I love it.
（前はあまり好きでなかったが、今は大好き）
There are many different ways to say this.
One common and informal way of saying this is, "I used to hate it, but now I love it."
"Use to" is used to show that something happened or was the case in the past but is no longer that way.
You can also say, "I didn't like it before, now I love it".
Also, if you want to express that you like something, you can say: hooked on it, keen on it, obsessed with it, or crazy about it.
For example: I didn't like it before, but now I am hooked on it.
I used to hate it, but now I am crazy about it.
これはいろいろな言い方ができます。
よく使われるインフォーマルな言い方としては、例えば：
"I used to hate it, but now I love it."
（以前はそれが嫌いだったが、今は大好きだ）
"used to" は、以前はそうであったが今は違うことを表す場合に使われます。
次のようにも言えます：
"I didn't like it before, now I love it"
（以前はそれが好きではなかったが、今は大好きだ）
あることが好きなことを表す場合、次の表現が使えます：
hooked on it, keen on it, obsessed with it, crazy about it
例文
I didn't like it before, but now I am hooked on it.
（以前はそれが好きではなかったが、今は大好きだ）
I used to hate it, but now I am crazy about it.
（以前はそれが嫌いだったが、今は大好きだ）
It didn't appeal to me at first but now I love it!
Initially I wasn't interested but now I am enamoured by it!
'Does not appeal.' We use this phrase when expressing that something is not attractive or interesting.
"Eating horse meat does not appeal to me."
To be enamoured = be filled with love for.
"it is not difficult to see why Edward is enamoured of her"
"I am totally enamoured by the idea of living and working in Italy!"
'Does not appeal.' ：魅力的に感じない、面白くない、というときに使う表現です。
"Eating horse meat does not appeal to me." 馬肉は別にそそられないね。
To be enamoured = -への愛でいっぱいだ。
"it is not difficult to see why Edward is enamoured of her"
なんでエドワードが彼女を愛しているのかわからない。
"I am totally enamoured by the idea of living and working in Italy!"
イタリアに住んで働くっていうアイディアに心が惹かれている。
I wasn't into that hobby before, but now I'm obsessed!
I really didn't like that hobby, but now I love it!
The two sentences you see above are terrific ways to express to someone that you now like something that you did not like in the past. In the first sentence you will see the term into something. When we are into something it means we really like or enjoy something in particular. This is a term we use in our everyday conversation and it would make a great addition to your vocabulary!
I was not into it when I first started but now I'm enjoying it
When you want to explain that you were not interested in something before but now love it, then you can explain it in the following ways:
-I wasn't interested at first, but now I love it.
-I was not into it when I first started but now I'm enjoying it
物事について、以前は興味がなかったけど今は大好きだと伝えたいなら、以下のような言い方ができます：
I wasn't interested at first, but now I love it.
（最初は興味がなかったけれども、今は大好きです。）
I was not into it when I first started but now I'm enjoying it
（始めた当初は興味がなかったけれども、今は楽しんでいます。）
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