Alan's crossword (6)

123456
Across
  1. 3. to follow
  2. 5. to go off and then on quickly (light)
  3. 6. easy to see
Down
  1. 1. biology and chemistry; the study of how things work
  2. 2. particularly this one
  3. 3. correctly or precisely
  4. 4. classes in school i.e. maths, English