虛度光陰

to waste time on worthless activities

emptiness / void / abstract theory or guiding principles / empty or unoccupied / diffident or timid / false / humble or modest / (of health) weak / virtual / in vain

to fritter away (one's time)

to pass / to spend (time) / measure / limit / extent / degree of intensity / degree (angles, temperature etc) / kilowatt-hour / classifier for events and occurrences

to estimate / Taiwan pr. [duo4]

light / ray / CL:道[dao4] / bright / only / merely / to use up

time available

surname Yin

overcast (weather) / cloudy / shady / Yin (the negative principle of Yin and Yang) / negative (electric.) / feminine / moon / implicit / hidden / genitalia