We should limit our emission that pollute the air, the land and the water. We can replace traditionnal cars with electric ones, bicycles, tracking (?) on short distances, etc. We should not throw plastics or glass or paper away away but instead recycle them. Industrial waste water must be treated before being introduced into our waterways preventing these toxins from poisoning our bodies and our environment.

Hello! The correct sentence is: that is familiar to you.

Hello! Must means that it is something you are required to do. Should means that it is something that would be best if you did but you are not required to do it. For example: I must go to the grocery store or we will not have food to eat for dinner.. Or, I should go to the grocery store so we have food for dinner tonight, but if I don’t, we can eat the pasta in the refrigerator. Does that help?

It’s better not to use. It’s not a proper way to speak. It replaces “I am not” or “she is not” but it’s better to omit from our vocabulary unless you are writing a story and it adds value. Hope this helps.

Can you share the context Julie as its hard to say. Thanks!