How clouds form For water vapor to condense in clouds, particles so small they can be seen only through a microscope must be present.
(clouds; form; ) (they; can be seen; ) (particles so small they can be seen only through a microscope; must be; present; T:How clouds form For water vapor to condense in clouds)
clouds they particles so small they can be seen only through a microscope
form can be seen must be
present T:How clouds form For water vapor to condense in clouds