Infectious bursal disease virus ( IBDV ) is an important pathogenic agent of chicken.传染性法氏囊 病毒是鸡的一种重要的病原.The distribution and histology of lymphoid tissue in the Fabricius'bursal stalk were studied.研究了番鸭法氏囊柄部淋巴组织的分布...
阿富汗空军正用直升机向被围城镇提供补给。The Afghan air force was using helicopters to supply the besieged town.这些补给要卸下来装上直升机。The supplies need to be offloaded and put on helicopters.各种补给都不稳定，食品也短缺。Supplies of everything are unreliable, food...
你坐在你哥哥的摩托车后面时,要抓牢.Hold tight when you ride at the back of your brother's scooter.我拼命地抓牢树枝.I clung onto the branch for my life.他紧紧抓牢绳子.He kept a fast hold on the rope....