three-fourths of the surface of the earth ( ) sea 是is 还是are?

three-fourths of the surface of the earth ( ) sea 是is 还是are? three-fourths of the surface of the earth ( ) sea （）of its surface of the earth is sea. "Nearly three fourths of the earth"做主语时,谓语用单还是复啊? Three fourths of the population of china are farmers. Three fourths of the students are from China. Nearly three-quarters of the earth's surface are covered wit Three fourths of the land____ with trees.A.are covered B.is three quarters of the earth's surface is covered with water. three fourths of the homework have finished Three-fourths of the buildings was destroyed. Three fourths of the homework ( )toda