Just one of my charts to help students learn the tenses.

1. Simple Present Tense Verb “to be”(ser;estar; tener años;tenerfrío;hambre,sueño,etc; costar; medir; salir; quedar ;
hallarse ; existir; constituir etc,etc.
Time reference:Inflexions: be-am-is-are-was-were-being-been
To be or not to be; that is the question.
Affirmative Negative What Interrogative
Form Y Form Which Form
I am e I am not Whom  I ? //
Whose
You are S, You are not you ? / /
Where
He is __ He When he ? //
She is She is not How
Who __ It How many
 she ?//
It is
How much It ? //
How long
We are
No, We are not
How often we ?//
You are __ You are not Why you ? //
They are
__ They are not they ? //
__ 
 Contractions: ’m ’s ’re
isn’t aren’t

This chart is designed for students to learn the verb to be in all forms and most wh questions. It is intended to be cut and pasted on a cardboard sheet or similar stuff: In Yes and No answers the dashes represent
pronoun operator (not). Phonetic transcriptions can be appreciated if you have silpa fonts, though the document has font embedment.
I hope you will find it useful. Prof. Stella Maris Berdaxagar Quemú Quemú La Pampa Argentina
http://smberdaxagar2010.wordpress.com/