一般单位体积重量愈()的土壤挖掘也愈困难。
A、小
B、大
参考答案:B
0号柴油中的0表示()。
A.蒸发性
B.粘度
C.凝点
D.发火性
In the Oral Approach language teaching begins with the spoken language. Material is taught orally before it is presented in the ______ form.