彼（かれ）はこのごろ頭（あたま）がぼけてきた。

He had grown senile recently.

台所（だいどころ）でころんで以来（いらい）彼女（かのじょ）はぼけてしまった。

Ever since she fell in the kitchen, she hasn't been all there.

最近（さいきん）、物忘（ものわす）れが激（はげ）しくて。少（すこ）しボケてきたのかな？

Could I be going soft in the head? I forget things so easily these days.