既然考据
幼苗
共回答了20个问题采纳率:85% 举报
three safeguards :safety cap,safety belt,and safety net
four holes:stairs exit,elevator well hole,reserved construction hole,and passageway exit
five critical edges:the balcony without handrails,the construction layer without peripheral protection,the edges of the frame structure construction layer ,both sides of the up-down runway and ramps,and the edges of the unloading platform
1年前
1