3、sand的复数形式thousands意为“数千;成千上万的,常和介词of连用,其前不可以受表示具体数字的词修饰。e.g.Therearethousandsofbuildingsinthisbigcity.@.Ononehand,morethanthreequartersofthepopulationareChinese…Ontheotherhand…ontheonehand…ontheotherhand一方面……另一方面……e.g.On the one hand, she taught English,on the