Am/is/are - формы глагола BE (быть) во временах Present
когда говоришь о себе - am ( I am friendly)
когда говоришь мы, они, вы, ты - are ( We are friendly, they are friendly, you are friendly)
когда говоришь он, она, оно - is (She is friendly, he is friendly, it is friendly)
was/were - формы глагола BE (быть) во временах Past
когда говоришь я, он, она, оно - was (I was friendly, he was friendly, she was friendly, it was friendly)
когда говоришь они, мы, вы, ты - were (They were frienly, we were friendly, you were friendly)
will используется во временах Future
Если ты хочешь сказать, что будешь что-то делать, то I will do it. (Я сделаю это)
Если ты хочешь сказать, что будешь каким-то, то I will be friendly. ( Я буду дружелюбным)
will на русский язык не переводится
глагол have имеет две формы
have для мы, ты, вы, я, они (We have it, you have it, I have it, they have it)
has для он, она, оно (She has it, he has it, it has it)
глагол have также может быть вспомогательным (Present Perfect), но принцип тот же:
have для мы, ты, вы, я, они (We/you/I/they have been there several times)
has для он, она, оно(He/she/it has been there several times)
do - для мы, ты, вы, я, они в Present Simple
(Do we/you/I/they like it? - We/you/I/they do it. - We/you/I/they do not like it.
does - для он, она, оно в Present Simple
(Does he/she it do it? - He/she/it does it. - He/she/it does not do it.)
did - для всех лиц и чисел в Past Simple
Did I/we/you/they/he/she/it do it yesterday?
I/we/you/they/he/she/it did it yesterday.
I/we/you/they/he/she/it did not do it yesterday.
can - для всех лиц и чисел в Present Simple
Can I/we/you/they/he/she/it do it?
I/we/you/they/he/she/it can do it.
I/we/you/they/he/she/it can not do it.
could - для всех лиц и чисел в Past Simple
Could I/we/you/they/he/she/it do it yesterday?
I/we/you/they/he/she/it could do yesterday.
I/we/you/they/he/she/it could not do it yesterday.
must - для всех лиц и чисел
Must I/we/you/they/he/she/it do it?
I/we/you/they/he/she/it must do it.
I/we/you/they/he/she/it must not do it.
should - для всех лиц и чисел
Should I/we/you/they/he/she/it do it?
I/we/you/they/he/she/it should do it.
I/we/you/they/he/she/it should not do it.