Can the verb following "depuis que" be in the present tense?

Hi Barbara,

yes, in fact, it can. Here is an example of a nice French idiom:

Depuis que les poules ont des dents. -- Literally: since hen have teeth. In English one would say, "since pigs can fly".

You use the indicative present tense when the action is still ongoing at the moment. In the example above it is implied that hen still have teeth now. You use the passé composé if the action is something that's a thing of the past, like in the following example.

Nous le savons depuis que tu nous l'as dit. -- We know it since you told us.

The action of telling us happened in the past and is not presently ongoing. This asks for the passé composé.

Greetings, -- Chris.

Interestingly one of the examples is actually not in the passé composé, even though the translation is in the past tense. Maybe the phrase "j'ai X ans" is an exception?

Depuis que j'ai quatre ans, je porte des lunettes.

Ever since I was four, I've been wearing glasses.