Contractions
You will want to learn how to use contractions as soon as possible. Contractions are used constantly in informal English. Examples of contracted subject/verb forms are:
TO BE:
I am-->I'm
he is-->he's
we are-->we're
you are-->you're
they are-->they're
TO HAVE:
I have-->I've
we have-->we've
you have-->you've
they have-->they've
Contractions are frequently used with compound forms of verbs, especially the progressive or continuous form of the present tense (I'm going. / We're leaving.) and the present perfect forms (I've received the letter. / They've already left.)

Asking Questions
In English, you can ask simple yes/no questions by either inverting the subject and verb or by using rising intonation:
--We can change money here.
(simple, declarative statement)
--Can we change money here?
(question with verb first)
--We can change money here?
(question with rising intonation)
NOTE: In the case of the simple present tense, it is necessary to use a form of the verb to do as an auxiliary in making a question:
-->They like this bank.
-->Do they like this bank?
--You have a passport.
-->Do you have a passport?

Information Questions
Many times you will want to ask a question that elicits information, instead of a simple yes/no answer. Information questions will begin with one of the following words:
WHO, WHERE, WHOM, WHAT, WHOSE, WHICH, WHY, HOW, WHEN

Who refers to people. It is used as the subject of the question.
Whom is used as the object of a verb or preposition.
Whose asks questions about possession.
Why is used to ask questions about reason.
When is used to ask questions about time.
Where is used to ask questions about place.
What can be used as the subject or object of a question. It refers to things.
Which is used instead of what when a question concerns choosing from a definite, known quantity or group.
How generally asks about manner. It is often used with much and many.
When a form of to be is the main verb in the simple present and simple past, it precedes the subject:
--Who is that man?
--Where is the airport?
--Where are the checks?
--What time is it?