If you don’t study English all the time, you’ll have a difficult time ____ it in the future.

A．studying

B．to studying

C．studied

D．be studying

报检单位在向出入境检验检疫机构报检注册登记，取得报检单位代码后，应在划定的区域内办理报检事项。需在异地办理报检手续的，应向报检地的检验检疫机构办理《出入境检验检疫报检注册登记证书》异地备案手续。( )