be on be on guardkeep guardstand guard意思都是相等的吗？可以做同义句吗？

be here on time同义句 Please be here on time.同义句 You must be on time for school.的同义句 be divided on的意思 be on什么意思 "be based on"与“be found on"都有"建立在.的基础上"的 意思,那他们有区别吗? be on the phone 和be talking on the phone意思一样吗 she is sure to be on time 同义句 英语be keen on三个同义句转换! My perents will be on holiday next week.同义句 同义句You shuld be on time for this meeting. I hope to be there on time中的be做什么将?是be动词吗?