Help, please! Are these sentences proper and grammarly correct?

Si tu reçois du courriel offensif, ne répond pas.
Lorsque tu t'inscris à une communauté virtuelle, ne partage jamais ton numéro.
Quand tu utilises un ordinateur public, se déconnecter de tous les comptes.

answer: how exactly do we answer this? we don't know anything about you and you are asking us about high schoolers taking french. (not to be rude) go ask some people in your school.

explanation:

answer:

au revoir! : )

explanation:

before arriving at the museum, we notice a charming alley, with its stream, breathtaking greenery, hundred-year-old trees, ducks and geese, sculptures of different themes.

this museum takes up the entire history of electricity from its beginning to the present day, we appreciate the exhibitions and the references to those who were the first to master electricity and exhibit many ancient instruments of electric hope. many films and audio recording available to explain the operation of the devices and each and translated into 3 languages. (english, french, german). the explanations are simple and can be understood even by a young audience. many games and experiences are available for self-made throughout the visit. the animation around static electricity is well done and generally delights children. there is also the "nostalgia" part in which we can find the household appliances of our youth, that of our parents, even of our grandparents. the setting is warm, informative and entertaining. the museum is quite well done in all. it provides useful knowledge on electricity.