下列树种,针叶为3针一束的是()。
A.樟子松
B.雪松
C.白皮松
D.红松
参考答案:C
Kathy _______ a lot of Spanish by playing with the native boys and girls.
A.picked up
B.took up
C.made up
D.turned up
将
展成x+1的幂级数,