So far you have met the preposition cum which means “with”:
 

Marcus cum amicis ad forum venit.

Marcus went to the forum with his friends.

visne Romam mecum ire?

Do you want to go to Rome with me?

 
Now you need to learn the conjunction cum which means “when”:
 

cum nuntius nobis rem naravisset, statim discessit.

When the messenger had told us the account, he left immediately.

 
Notice that the verb in the cum clause has the ending “-isset”. This is called the pluperfect subjunctive (the plural ending is “-issent”). For translation purposes, it should be dealt with in the same way as a normal pluperfect tense (e.g. narraverat).
 
 
Now try the following examples:
 

1. cum agricola cenam consumpsisset, fur villam intravit.

2. cum uxor ad villam revenisset, maritus ei cenam paravit.

3. cum iter in nave fecissemus, milites urbem nostram delebant.

4. cum iuvenes ad aulam pervenissent, regem reginamque salutaverunt.