be present at意思

be present at意思 at present,must to be. at the present time 和at present一个意思吗 有关be present at的用法 All____will be present at the conference. at present,in present,for present,with present的各个意思及用法 in the present,at the present分别为什么意思?还有：in the present,at pr 问下哈at a present什么意思 Applicants must be present at event to be considered present tense to be 的意思是什么? present tense to be什么意思? present at 与 be present at 有什么区别? 怎么用 什么时候不能互换?