People with a fear of heights often go weak at the knees on a glass skywalk.
Tips
usage
Casual speech often drops the 症: 我恐高 "I'm scared of heights". Other phobias put the feared thing before 恐惧症 "phobia", as in 幽闭恐惧症 (claustrophobia), 社交恐惧症 (social phobia), shortened online to 社恐.
