When walking on campus,it is necessary to walk around many fences_英语解答

When walking on campus,it is necessary to walk around many fences and barriers.请问是简单句还是复
句,为什么

人气：358 ℃　时间：2020-05-19 10:15:20

解答

复合句,前面的When walking on campus是状语从句＝ When you are walking on campus