Bộ 40 đề thi Tiếng Anh vào 10 có đáp án - Đề 34

All motorcyclists must wear helmets. It is…………....for them to wear helmets.

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All motorcyclists must wear helmets. It is…………....for them to wear helmets.

official

compulsory

optional

separate

Giải thích

Đáp án D