Directives

Directives are sentences which instruct someone to do something. To call them commands is misleading, because commands are one type of directive. 

Here are some examples:

Commanding - Sit down now!

Inviting - Have a drink with me tonight. 

Warning - Mind where you tread.

Pleading - Help me.

Advising - Take the medicine.

Requesting - Open the door, please.

Expressing good wishes - Have a nice day.

In all of these cases, the verb is in it's basic form, with no endings, and there is usually no subject element present. Sentences structured in this way are called imperatives. It is typical for a directive sentence to have an imperative structure. 

Some directives do not use the basic pattern. 

They allow a subject with strong stress - You be quiet! Nobody move! Everyone go!

They begin with let followed by a subject - Let me see. Let us pray. Let's go.

They begin with do or don't - Do come in. Don't laugh. Do not answer. 

Questions

Questions are sentences that seek information. There are three main types, dependant on the kind of reply they expect and their construction. These type of sentences are said to have an interrogative structure. 

Yes-no questions

'Are you ready?' 'Do you want dinner?'

Wh- questions

What, why, where and how questions.

'What time is it?' 'How are you today?'

Alternative questions

Requires an option to be selected. They always have the connecting word 'or' in them.

'Would you like eggs or bacon?' 'Manchester City or Manchester United?'

Statements can be turned into questions by a tone of voice. 

'John's home?' 'You've spoken to him?'

Tag questions

These are questions where the interrogative structure is added at the end of the sentence. 

'You like ice cream, don't you?' 

These questions also expect a 'yes' or 'no' reply.

Exclamatory questions

These are questions that are an exclamation and ask the hearer to agree. 

'Hasn't she grown!' 'Wasn't the book marvellous!'

Rhetorical questions

These are questions that don't expect an answer. 

'Who cares?' 'How should I know?' 'What difference does it make?'

Intonation

If we change the intonation of a question it can alter it's meaning. 

'She's not in, is she?' (I want to know - The tone at the end is rising)

'She's not in, is she!' (I told you so - The tone at the end is falling.)

This can be unclear when written down, so be careful.