Most use other substances as well, so it is important to be able to intervene for a variety of problems.
It's important to know as much as possible about other substances.
It is only required to know about one substance.
A little boy climbs a small hill.
There is a group of people playing football.
Viking fan is who I am.
Lacrosse players are going after a ball
Girls playing soccer.
Two people working in an office.