am / is / are are verb be generally present tense, meaning is "YES", the three different main difference is in case of use.
First, when the subject is a personal pronoun
1, am: the subject is first person
Examples: I am a student (I am a student.).
2, are: the subject is the second person
Examples: They are my parents (they are my parents.).
3, is: the subject is third person
Examples: He is an English boy (he is an English boy.).
Second, when the subject is a noun
1, are: the subject is plural noun
Examples: These pens are hers (which is her pen.).
2, is: the subject is singular or uncountable nouns
Examples: The pen is mine (this is my pen.).
Three: BE verb other forms
First, the simple past:
The first person singular and the third person singular form, the use was.
And the first person plural second person plural, third person plural, then use were.
Second-person singular also use were.
Second, future tense
will be: will the equivalent in general be going to, indicate what will be done, there will be more colloquial nuances between the two points, be going to represent likely soon to begin to do.
