Nyelvtanilag helyesek ezek az angol mondatok? (lent)

A car legyen többes számban, a people elé kéne egy vessző.

greenhouse effect is high

Nyelvtanilag jó, de műszakilag nem igazán. Az üvegházhatás nem lehet magas vagy alacsony.

Cities have a large number of cars that cause traffic fumes which increase the carbon dioxide in the air. I believe this is one of the reasons why we have such high level of global warming today.

In the country side, the life expectancy is higher than in the polluted cities. People in smaller towns are living longer due to fresh air and more peaceful lifestyles.

1es: "Nyelvtanilag jó..." - sajnos tevedsz, nem jo!

Amit a 4es irt az jo, de o atirta a mondatokat, plusz az uccso mondata hibas.

Itt a te mondataidnak a javitasa es a magyarazat:

In the city, there are a lot of cars that produce traffic fumes (cause traffic jam - kozuti forgalmat okozni, de fustot nem okoznak, hanem produkalnak), which increase the level of carbon dioxide in the air.

I think (And-el nem kezdunk mondatot) that is the reason why greenhouse gases are so high nowadays. (nem a greehouse effect a magas, hanem a gazoknak a szintje novekszik)

In the countryside, the life expectancy is higher than in the cities. People live healtier because they have a peaceful life.

Nem living healthier hanem live, egyszeru jelen.

De ertelmetlen: nem azert elnek tovabb mert bekeben elnek, hanem mert tisztabb a levego, nem? Ebben az esetben People live healthier because the air is cleaner.