Vaccination and other prophylactic measures can be carried out.可以采取疫苗接种和其他预防措施。Anyone who wants to avoid the flu should consider getting a vaccination.如果不想得流感，就该考虑接种疫苗。Smallpox can be contained by vaccination.种牛痘疫苗可以控制住天...
Reasons of forming first cracks were foundry lacuna, impurity gathering , lard exiting.铸造缺陷 、 杂质元素偏聚和夹杂物的存在是形成早期裂纹源的原因.There was so much very deep lacuna in his crude big hands.粗糙的大手上一道道很深的裂口.Objective To investigate the...