The basic structure we use to say “before” is:
【Subsequent Action】前に【Prior Action】
Both the subsequent and prior actions will be independent clauses and thus end, like all sentences, in a verb. The verb for the subsequent action must be the present tense dictionary form. This is a little confusing for English-speakers because in English we put each clause in the tense corresponding to the timing of the action relative to the present. In other words, we would say:
Before I went to work I bought some cigarettes.
In Japanese, however, the tense of the first clause is independent from the tense of the latter.
|Before I go to work I will drink coffee.|
|Before I went to work I drank coffee.|
As a native English speaker there is an innate desire to say:
Unfortunately, this is not correct.
|Turn off the lights before leaving the house.|
|Look left and right before crossing the street.|
|Please come back home before it gets dark.|
For nouns we need to use the possessive particle, の.
|Please make sure you call before 9am.|
|Before the seminar please register your name at the reception.|