the first period 是名词性短语 during the first period 是介词短语
call in orders 按顺序打电话
on their room phones 是打他们的房间电话
用复数是因为学生是复数
一般通过电话是用介词on
仅供参考
the first period 是名词性短语 during the first period 是介词短语
call in orders 按顺序打电话
on their room phones 是打他们的房间电话
用复数是因为学生是复数
一般通过电话是用介词on
仅供参考