bàn tiān
前半天
qián bàn tiān
morning; first half of the day
后半天
hòu bàn tiān
afternoon; second half of the day
用半天时间就可以把活儿干完。
yòng bàn tiān shí jiān jiù kě yǐ bǎ huó er gàn wán
The work can be finished in half a day