The digraph /er/ making the sound "eh" as in teacher.

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Across
  1. 3. Will not happen at all.
  2. 4. An unhappy feeling.
  3. 7. Another word for bigger.
  4. 9. The person who helps you learn.
  5. 10. Of higher quality.
Down
  1. 1. You climb up this to reach something.
  2. 2. The season after autumn.
  3. 5. Sparkly stuff used in craft.
  4. 6. The opposite of under.
  5. 8. The Darling _____ flows through Louth.