気を散らす
to take care of anything―be careful of anything―give attention to details―pay attention to a lecture―note a fact―take note of a fact―mind one's business
to dissipate one's melancholy―dispel one's gloom―chase one's gloom away―divert one's mind―amuse oneself
to have a heavy heart―be heavy-hearted―be depressed in spirits―be in low spirits―be in the dumps―be in the blues―have a fit of the blues―be grave―be pensive―be melancholy
to be anxious about something