"the job will take more than an hour"
"the hour is getting late"
"it was their finest hour"
"we live an hour from the airport" "its just 10 minutes away"
误 The whole thing was held up about half of an hour〔half hour〕.
正 The whole thing was held up about half an hour〔a half hour〕.
析 “半个小时”通常说half an hour或者a half hour,而不说half of an hour或者half hour。
