$\text{Answers:}$

It's against the rules for young children to drive beyond the speed limit. (must)
=> Young children must not drive beyond the speed limit.

$\text{-}$ It's against the rules for sb to V_inf: Đó là phạm luật với ai đó khi làm gì

$\text{-}$ S + must not V_inf: Ai đó tuyệt đối không được làm gì
It's healthy to eat fruit and vegetables. (should)
=> We should eat fruit and vegetables.

$\text{-}$ It's healthy to V_inf: Thật lành mạnh khi làm gì

$\text{-}$ S + should V_inf: Ai đó nên làm gì

`\color{yellow}{Tuancute}`

1. Young children must not drive beyond the speed limit as it is against the rules

- It's against the rules + for O + to V: Làm điều gì là trái luật

-> S + mustn't + V - inf: Ai đó không được làm gì

2. You should eat fruit and vegetables

- It + tobe + adj + ( for O ) + to V

- S + should + V - inf: Nên làm gì