A. Two thousands B. Thousands of C. Two thousands of D. Thousand of

【答案】B

【解析】

句子意思是: ......树被砍到. 这里是短语thousands of(许多;数以千计的), 短语前不加数词, thousand单独用时不用复数, 组成短语thousands of时必须用复数. 因此A选项, C选项和D选项结构都不正确. 故答案为: B.