Verified answer

Ответ:

1. They shouldn't get married at 18. They are far too immature to take such an important decision.

immature - несозревший (юный)

2. She enjoys hot air ballooning and parachute jumping. She's very adventurous

adventurous - авантюрный

3. You aren't allowed to park here. Can't you see the sign?

to be allowed - разрешено (делать что-то)