Subject + 在 + 散步
散步 (sànbù) is a verb-object compound meaning "to take a walk" or "to stroll." Like other verb-object compounds, it does not take a direct object after it. For example, 人们在散步 means "people are taking a walk."
吃完晚饭,我们一起去散步吧。
Chī wán wǎnfàn, wǒmen yìqǐ qù sànbù ba.
After dinner, let's go for a walk together.
爷爷每天早上都要去公园散步。
Yéye měi tiān zǎoshang dōu yào qù gōngyuán sànbù.
Grandpa goes for a walk in the park every morning.
她喜欢在海边散步,觉得很放松。
Tā xǐhuan zài hǎibiān sànbù, juéde hěn fàngsōng.
She likes walking by the seaside and finds it very relaxing.