—What’s his monthly income?

—Well, he ________ earn as ________ as 4,000 dollars a month when his business runs well.

A．can; much

B．might; many

C．must; far

D．should; high

牛的静脉注射，多采用（）

A.颈静脉

B.耳静脉

C.前腔静脉

D.小隐静脉