Sentence:  And then again perhaps the reason why he could n't find time to do any of the things he had planned to do after retirement : reading , <WSD>roaming</WSD> , gardening , lying on his back and watching the clouds go by , was because he did n't want to do them . 
Meaning of the word marked with <WSD> tags:  move about aimlessly or without any destination, often in search of food or employment