医 旧结核菌素

*[æt]
prep. 在, 向, 对
计 地址转换器, 异常传输, 自动订票
医 砹(85号元素)
相关词组:
at war
at regular intervals
at peace
to keep on at sb
at midnight
at the moment
be at an utter loss what to do
at work
at school
at rest