In order to explain that you are not good at sports that use a ball because you personally have a fear of sports involving a ball, you can simply state "I'm afraid of the ball" or "I'm scared of the ball". Both these sentences are effective as they direct address what you do not like about these types of sports and that you do not want to play them due to your fear.
ボールを使ったスポーツは怖いので苦手だと伝えたいなら、次のように言えます。
"I'm afraid of the ball"（ボールが怖いです）
"I'm scared of the ball"（ボールが怖いです）
これらの文はどちらも、ボールを使ったスポーツのどこが苦手なのかをストレートに伝えていて効果的です。
You could simply state 'I am afraid of the ball' or you could say it in another way 'the ball scares me' or if you wanted to go into more detail you could talk about why you are afraid of the ball.
'I am afraid of the ball hitting me/hurting me/hitting my face'. This gets the message across quicker as it saves the person then asking you why you are afraid of the ball.
シンプルに 'I am afraid of the ball'（ボールが怖いです）と言えます。
また、 'The ball scares me'（ボールが怖いです）という言い方もできます。
もっと詳しく言いたいなら、ボールが怖い理由を伝えることもできます。
'I am afraid of the ball hitting me/hurting me/hitting my face'.
（ボールが当たる/ボールでけがをする/ボールが顔に当たるのが怖いです）
このように言うと、相手はボールを怖がる理由を尋ねる必要がなくなり、より素早く言いたいことが伝えられます。
I'm useless at ball sports as I'm scared of the ball
If you are not good at sports that use a ball and you wish to explain that it's because you are afraid of the ball, then simply use the above exampled sentence which is more than appropriate! If you are 'useless at..' something it means that you have no talent or skill in this regard.
To explain why you are not good at playing sports that use a ball, you can simply use these expressions to express it is because you are scared of the ball.
-The ball scares me.
-I am afraid of the ball.
-I have a fear of the ball.
「ボールが怖い」ので球技は苦手だと説明するなら、これらの表現が使えます。
-The ball scares me.
-I am afraid of the ball.
-I have a fear of the ball.
（ボールが怖いです）
I'm not very athletic when it comes to sports that use a ball
You may be a strong swimmer or a good at running, but basketball and baseball are difficult. If you want to say this the best way is "I'm not very athletic when it comes to sports that use a ball". This let's people know that you aren't good. If you want to tell them why you can include it is because you are afraid of the ball but it's not necessary.
あなたは水泳やランニングが得意かもしれませんが、バスケットボールや野球は難しいと思うかもしれません。このことを言うには、
"I'm not very athletic when it comes to sports that use a ball"
（ボール競技は得意ではありません。）
と言うのがいいでしょう。これは、相手にボールの競技が得意でないことを伝えることができます。どうして得意でないかを伝えたかったら、伝えてもいいですが、ボールが怖いからと言うのは必ずしも伝えなくてもいいでしょう。
The two sentences you see provided above are excellent ways to express to your listener that you are afraid of the ball. In the second sentence you will see the word intimidate. This means to be afraid of something because of what it can do to us. This word is appropriate for both formal and informal settings, it would make a great addition to your vocabulary.
If you don't like something and it makes you feel nervous then you would say you are 'afraid' or 'scared' so you would simply say
'I'm afraid of the ball' or 'I'm scared of the ball'
苦手で怖いものは 'I'm afraid' や 'I'm scared' で表すことができます。
ですからシンプルに、
'I'm afraid of the ball'（ボールが怖いです）
または
'I'm scared of the ball'（ボールが怖いです）
と言えます。
When you want to express to someone that your afraid of something, There are a few words to describe fear a few would be Afraid,Scared and frightened. So when your asked why you are not good at sports that use a ball you could say "The ball frightens me" or "The ball scares me".
「～が怖い」の「怖い」はいくつかの言葉で表すことができます。
例えば：'Afraid' 'Scared' 'Frightened'
なぜ球技が苦手なのか聞かれたら、次のように言えます。
"The ball frightens me"
"The ball scares me"
（ボールが怖い）
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