The deputy prime minister has raised the prospect of a trans-Tasman bubble once both Australia and New Zealand have the virus tightly under control. That could also include some Pacific countries-provided it does not burst. 请问第二句话中 provided... 充当的是什么成分,怎么样理解这个使用方法与句意。
provided在此为连词,引导条件状语从句,为正式语体使用方法,意义等于 if.
That could also include some Pacific countries--provided it does not burst.
= That could also include some Pacific countries--if it does not burst.