I am afraid what you posted is quite cryptic - I bet English is not your first language.
But first things first - can you write formulas for all compounds listed? Magnesium oxide, magnesium nitride, magnesium hydroxide and magnesium carbonate?
Can you then write skeletal (unbalanced) equations for all reactions listed? For example - when magnesium is burnt in the air, one of the products is magnesium oxide, can you write skeletal equation for this reaction?