不是纵隔内结构的是()
A.心包
B.心脏
C.心脏大血管
D.气管
E.脊柱胸段
参考答案:E
原核生物中具有GTP酶活性的翻译起始因子是
A.IF1
B.IF2
C.IF3
D.eIF1
E.eIF2
________it was ________so many elephants marching along the street.
A.How great fun; to see
B.What a great fun; seeing
C.What great fun; to see
D.How great a fun; to see.