How to tell the time

Explanation

There are two common ways of telling the time.

Formal but easier way

Say the hours first and then the minutes.

Example: 7:45 -It's quarter to eight

For minutes 01 through 09, you can pronounce the '0' as oh.

Example: 11:06 - eleven (oh) six

More popular way

Say the minutes first and then the hours. Use past and the preceding hour for minutes 01 through 30. Use to and the forthcoming hour for minutes 31 through 59, but .

Example: 7.15 - fifteen minutes past seven

Example: 7.45 - fifteen minutes to eight

Another possibility of saying '15 minutes past' is: a quarter past

Another possibility of saying '15 minutes to' is: a quarter to

Another possibility of saying '30 minutes past' is: half past

Example: 5:30 - half past five

Watch

Note

Use o'clock only at the full hour.

Example: 7:00 - seven o'clock (but 7:10 - ten past seven)

For times around midnight or midday you can use the expressions midnight or midday / noon instead of the number 12.

Beispiel: 00:00 - midnight

Beispiel: 12:00 - midday or noon

It is not usual to use a.m. and p.m. with past/to.

Example: 3:15 - fifteen minutes past three OR a quarter past three

American English

Beside past Americans often use after.

Example: 06:10 - ten past/after six

But: in time expressions with half past it is not usual to replace past by after.

Beside to Americans often use before, of or till.

Example: 05:50 - ten to/before/of/till six

Link: 

http://www.teachingtime.co.uk/clock2/clockwordsres.html

http://www.comunicaciodigital.com/english_clock/englishclock.htm