I am going to school. I going to school. как понять когда надо ставить am, ну и подобные is , are. И еще они ставятся в каком то определенном времени или во всех?

I going to school - неправильно. В конструкции "to be going to" есть 'to be', следовательно 'to be' должно менятся в зависимости от лица.

Am/is/are может быть или глаголом-связкой в Present Simple; или вс глаголом в Present Continious Active, Present Simple Passive, Present Continuous Passive, а также в конструкции to be + to + Infinitive (в будущем).

I + am (am not)

You, we, they + are (are not)

He, she, it + is (is not)

it seems to me that not everyone thinks about what he or she eats and it ii really bad.our health depends on food we eat every day.our organism needs different vitamins,proteins,fats and othersubstances. to feel good we should eat products which are rich in all this elements/

secondly, the next important question is the combination of different products. separate nourishment is very useful for people(апостроф)s health

thirdly, everybody also should follow a diet which would be healthy. some of them help people to loose weight,other-to treat diseases. all of us ought to follow such diet which includes a daily menuof such products as meat, fish,fruits,vegetables and milk