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Virtually any preposition.

You can think about it as following. Preposition requires an expression in some specific case (case gives an additional information). But verbs can't take cases so...

1.До того, как я поеду в Россию я хочу выучить русский = Before I go to Russian I want to learn Russian.
2. Она ушла перед тем, как я приехал = She had left (immediately) before I arrived
3....

In short most often "до" describes time sequence, while "перед" - space position (="in front of").

If "перед" is used for time sequence then it means "right before", "immediately before". If "до"...