hours什么意思,hours怎么读

after working for three hours, he began having rest.
hour's,hours'和hours都表示小时,区别在于具体形式和意思: 1,形式
the13-inchmodellastedsixhoursand13minutes,versusapple'sclaimofup
六年级英语下册he spent about twenty-one hours in
it took the students about hours to finish their experiment.