laura.nicole said:
i think my teacher said something about people on the street selling pens to make a job for themselves...would that be underemployment?
That would be them creating a job in the informal market (which basically means they are just selling stuff off for cash to live, it's not a proper business that's taxed etc), which is a result of under-employment. If under-employment wasn't an issue, people wouldn't have such a hard time finding a job in the formal sector, but there are only so many jobs, and there are more people than employment positions.
EDIT: Just looking it up further, there is actually a couple definitions for under-employment. Another meaning for it is people who have the skills for a good job, but they can't find a job to use those skills in, so they result in something anyone could do (selling pens). I believe this isn't the definition that should be used with mega cities though (at least, for Mexico City - not sure what city you are doing) as most unemployed people are those that travel from rural areas to the city looking for work, but are underqualified for the few jobs that are available hence end up unemployed.