英語と日本語。
先ず英語。
理解できれば、あなたの英語力がアップした証（あかし）。

Two chemists walk into a bar.
One says, “I’ll have an ‎H2O.”
The other says, “I’ll have an ‎H2O, too.”
The second chemist dies.
H2O2 is the chemical formula for hydrogen peroxide, which you can’t drink at a bar without grievous consequ