Conditionals are formed by two different sentences. The first is the condition preceded by IF, the second is the result of that condition.Have a look at the different tenses used in the First Conditional:

IF + PRESENT TENSE , PRESENT TENSE/FUTURE SIMPLE

Now have a look at the videos:

[kml_flashembed movie="http://www.youtube.com/v/ow8FIHbwekU" width="425" height="350" wmode="transparent" /]

[kml_flashembed movie="http://www.youtube.com/v/CdHbkjCviC0" width="425" height="350" wmode="transparent" /]