蚊かに刺さされた、かゆくてかいちゃった。

ka ni sasareta, kayukute kaichatta.

I got a mosquito bite and scratched it because it was itchy. casual

犬いぬは耳みみの後うしろをよくかきます。

inu wa mimi no ushiro o yoku kakimasu.

Dogs often scratch behind their ears. neutral