干式检验使用的磁粉形状最好是（）。
A.细长型
B.球形
C.扁形
D.细长和球形的混合物
参考答案：D
杏仁龙胆草泡散功效与作用
Mr Sun is helpful and he _______ help others at any time. [ ]
A. is ready for
B. is ready to
B. is willing for
C. is getting ready to
