It's OK, it was already damaged before you touched it
If a friend apologizes for breaking something, but the item was actually broken before and you want to explain this, there are two functions your comment should include:
1. To placate your friend/allay his concerns.
2. To explain the details.
1.:'It's not a problem'/'Don't worry!'/'Relax!'
2. 'It was already like that/damaged/broken/' etc
友達が何かを壊してしまったと謝ってきたときに、それは前から壊れていたと説明したいなら、そこには二つの機能を持たせる必要があります。
1. 友達をなだめる/安心させる
2. 詳細を伝える
1. 'It's not a problem'/'Don't worry!'/'Relax!'（大丈夫だよ/心配しないで/大丈夫だから）
2. 'It was already like that/damaged/broken/' etc（最初からそうだったから/壊れていたから/など）
Its not a problem buddy, it was already a bit broken.
▪Don't worry, it was already halfway broken.
>"don't worry" means not to get anxious or feel that there will be a problem.
>"halfway broken" means that a part of the item was already broken before your friend broke it further.
▪It's not a problem buddy, it was already a bit broken.
>"buddy" is a casual word for friend.
>"not a problem" is indicating that you are not upset and that it is all okay.
【例】
▪Don't worry, it was already halfway broken.
（大丈夫、それ半分壊れかけてたから）
>"don't worry"とは心配しないで/大丈夫だから問題ないです、
という様な意味になります。
>"halfway broken"とは、友達が触る前から、
それは半分/部分的に壊れかけていた、という意味になります。
【例】
▪It's not a problem buddy, it was already a bit broken.
（問題ないよ、友よ、それ少し壊れてたから）
>"buddy" とはカジュアルな表現で友達という意味になります。
>"not a problem"とは、あなたは怒っていないし、大丈夫、何の問題もない、という事を表現しています。
Thank you for telling me but it was already broken before you touched it.
Oh that's ok, it was already broken.
I broke that myself the other day so don't worry about it.
Most people have a hard time telling someone they broke something so it helps to let them know if it was already broken and thanking them for telling you encourages them to be honest with you in the future.
Thank you for telling me but it was already broken before you touched it.
Oh that's ok, it was already broken.
I broke that myself the other day so don't worry about it.
何かを壊してしまったことを打ち明けるのは簡単ではありません。ですから、もともと壊れていたのならそのように伝えてあげると気持ちが楽になるでしょう。また、話してくれてありがとうと伝えれば、これから先も正直に言おうという気持ちになると思います。
Thank you for telling me but it was already broken before you touched it.
（教えてくれてありがとう、でもそれもともと壊れていたんだ）
Oh that's ok, it was already broken.
（大丈夫だよ、もともと壊れていたら）
I broke that myself the other day so don't worry about it.
（それこの間私が壊したんだ。だから、気にしないで）
If someone damages something of yours even by accident they will feel really bad so it's always good to make them feel better 'don't worry' or 'don't panic' are good ways to let them know it's not a problem
The two sentences you see provided above are excellent ways to express to your listener that an item they thought they broke was already broken. In the first sentence you will see the word ago. This means in the past. This word is commonly used in both formal and informal settings, it would make a great addition to your vocabulary.
Saying "Don't worry" after someone has apologised suggests that they didn't need to apologise or that you have forgiven them. Then, if you say "it was already broken" suggests that the item was broken before they broke it.
誰かに謝られた後 "Don't worry"（心配しないで）と言うと、「謝る必要はない」もしくは「許した」という意味になります。
そして、"it was already broken"（もともと壊れていた）で、それがその人が壊す前から壊れていたことを伝えています。
To explain that it was broken before, and that they did not break it, you can say:
"Don't stress, it was already broken."
"It was already broken, don't worry."
「これはあなたが壊したわけではなく、もともと壊れていた」は次のように言えます。
"Don't stress, it was already broken."（気にしないで、もともと壊れていたから）
"It was already broken, don't worry."（もともと壊れていたから、心配しないで）
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