一、填空题
1. $3\sqrt{7}+\sqrt{7}=$
2. $\sqrt{12}-2\sqrt{3}=$
3. $\sqrt{12}-\sqrt{27}=$
4. $\sqrt{32}-\sqrt{8}=$
5. $2\sqrt{\frac{1}{8}}-3\sqrt{2}=$
6. $\sqrt{125}-\sqrt{\frac{1}{5}}=$
7. $3\sqrt{\frac{1}{3}}-3\sqrt{12}=$
8. $\sqrt{18}-4\sqrt{\frac{1}{2}}=$

1. $4\sqrt{7}$
2. $0$
3. $-\sqrt{3}$
4. $2\sqrt{2}$
5. $-\frac{5\sqrt{2}}{2}$
6. $\frac{24\sqrt{5}}{5}$
7. $-5\sqrt{3}$
8. $\sqrt{2}$

二、计算题
9. $\sqrt{18} - \sqrt{8} +5\sqrt{2}$
10. $4\sqrt{\frac{1}{2}} +3\sqrt{\frac{1}{3}} -\sqrt{8}$
11. $2\sqrt{12} -6\sqrt{\frac{1}{3}} +3\sqrt{48}$
12. $3\sqrt{20} -\sqrt{45} +10\sqrt{\frac{1}{5}}$
13. $\sqrt{48} +2\sqrt{\frac{1}{3}} -\sqrt{12}$
14. $\sqrt{27} -15\sqrt{\frac{1}{3}} +\frac{1}{4}\sqrt{48}$
15. $\sqrt{\frac{2}{3}} -\sqrt{216} +24\sqrt{\frac{1}{6}}$
16. $(\sqrt{18} -2\sqrt{3}) - (\sqrt{\frac{1}{8}} -\sqrt{75})$

9. $6\sqrt{2}$
10. $\sqrt{3}$
11. $14\sqrt{3}$
12. $5\sqrt{5}$
13. $\frac{8\sqrt{3}}{3}$
14. $-\sqrt{3}$
15. $-\frac{5\sqrt{6}}{3}$
16. $\frac{11\sqrt{2}}{4}+3\sqrt{3}$