血液中能止血和吞噬病菌的血细胞分别是[ ]
A．血小板和红细胞
B．血小板和白细胞
C．白细胞和红细胞
D．白细胞和白细胞
答案：B
All this snow and ice makes it difficult for old people to ____ very well.
A．get around
B．go away
C．pick up
D．take off
根据黄连来源及产地的不同，商品上有味连、雅连和（）之分。
