English verbs have different forms in the simple present tense depending on the number and person of the subject. It is important that the verb and the subject agree. For the verb be these are:
Singular Present
I am 1st person
You are 2nd person
He is / she is / it is 3rd person
Singular Past
I was 1st person
You were 2nd person
He/she/it was 3rd person
Plural Present
We are 1st person
You are 2nd person
They are 3rd person
Plural Past
We were 1st person
You were 2nd person
They were 3rd person
Complete these sentences with the correc form of be: