按要求进行词形转换。
1. family (复数)___________      2. young(反义词) __________
3. short(反义词) ___________     4. meal(复数) ______________
5. know(同音词) ___________      6. active (反义词) ____________
7. Tuesday(复数) ___________     8. have (第三人称单数) __________
9. help(形容词) ___________      10. mountains（单数）___________