— It seems that Mr. Wu is standing there.— It ______ be him because he called me from Canada just now.
下列词语中划线的字,每对读音都不相同的一组是( )
有一个角是钝角的三角形,叫做钝角三角形.
下列关于培育良种“试管动物”的叙述,正确的是