[文法] 請高手指點，高中文法
這個文法應該是高中程度的，但我到現在始終不明白…請高手指點
Wang Mengshu, who is noted for his work on underground engineering, says
that rising costs mean that cities may not be able to complete work on new
systems or pay for their operation when trains have begun running.
王夢恕以地下工程見長，他表示上升的成本意味著各城市無法完成新的系統工程
或是在列車開通後負擔運作。
句子最後面 → when trains have begun running.
這個句子到底是用於未發生的假設語氣還是？
感謝指點，感激不盡
--
※ 發信站: 批踢踢實業坊(ptt.cc)
◆ From: 111.240.135.8
→
01/21 09:52, , 1F
01/21 09:52, 1F
→
01/21 09:54, , 2F
01/21 09:54, 2F