什么叫屈服强度？
参考答案：
指材料在出现屈服现象时所能承受的最大应力。
Nowadays, TV programmes _______ a lot of foreign language teaching ones, _______ English, Japanese, French and so on, of course _____ those for children.
A．contain; for example; include
B．include; such as; contain
C．contain; such as; including
D．include; for example; containing
动物细胞中cAMP信使的主要生物学功能是活化（）
A.蛋白激酶C
B.蛋白激酶A
C.蛋白激酶K
D.Ca2＋激酶
E.酪氨酸激酶
