Suppose you are going to Boston,and you have never v___ the city before.
Suppose you are going to Boston,and you have never v___ the city before ,if someone tells you about the interesting p____ in the city,you b___ to get some idea of what you will see.But you don't have a c___ idea of where these places are or of how to find t____.
However,i_____ someone has a map of the city and s______ you the main roads and buildings,you may say,"Oh,now I s_____.I can find my way with n_____ trouble at all."
Working in maths is a bit like trying to find your way a____ a new city.