decide upon
US /dɪˈsaɪd əˈpɑːn/
UK /dɪˈsaɪd əˈpɑːn/

1.
决定, 选择
to choose something or someone after careful thought
:
•
They finally decided upon a date for the wedding.
他们最终决定了婚礼日期。
•
We need to decide upon a course of action soon.
我们很快就需要决定行动方案。