ヘルメットを

helmet

→ ヘルメット
phrase Rare #32,329
helmet ヘルメット means “helmet,” and を marks it as the direct object of the verb that follows, such as かぶる (to wear) or 脱ぐ (to take off).
JA: ヘルメットをかぶってください。
EN: Please put on a helmet.

トムヘルメットをかぶっていればこんなひどい怪我ならなかったでしょうね

If Tom had been wearing a helmet, he probably wouldn’t have been so badly injured.

弾がヘルメットを通った

The bullet went through the helmet.

トムヘルメットをかぶる必要があるメアリー言った

Tom told Mary that she needed to wear a helmet.

トムヘルメットを着用していればあんな重傷負うことはなかっただろう

If Tom had been wearing a helmet, he probably wouldn’t have been so seriously injured.

彼にヘルメットを脱げと言える当然だ彼は死んでしまう

Of course, you could tell him to take off his helmet, but he’d die.

— オデッセイ (2015)