"However"
is a transitional word that moves your ideas from one sentence
to another. It's very similar to "but." It's used to show contrasts
and differences. "However" is also referred to as a conjunctive adverb.
examples
Having a car can
be very convenient; however, it's expensive to buy and maintain
one.
Walter has
a lot of work to do; however, he's too tired to finish it.
Jim
is in love with Graciella; however, he's not sure if she loves
him.
However hard she tried, she could not open the door
to get the office supplies.
However = No matter how
No matter how hard she tried, she ....
Bill doesn't mind working late; however, he's a little
scared of walking home by himself at this time of the night.
Beekeeping is an important
occupation; however, the beekeeper must keep himself covered
at all times.