# an ark

This refers to a very large box that would be able to float on water even in a very bad storm. "a large boat" or "a ship" or "a barge"

# cypress wood

People do not know exactly what kind of tree this was. "wood used for building boats" or "good wood"

# cover it with pitch

"spread pitch on it" or "paint tar on it" or "cover it with pitch to make it waterproof" 

# pitch

This is a thick, sticky or oily liquid that people put on the outside of a boat to stop water from going through gaps in the wood into the boat.