Example sentences
nǐ你shén什me么shí时hòu候zǒu走？
When are you leaving?
xiǎo小shí时hòu候wǒ我zhù住zhè这ér儿。
I lived here as a kid.
About this word
时 is "time, season" and 候 is "to wait, to watch for", also used for seasons and climate. Together they name a particular point or occasion. The grammar is the important part: 时候 almost never stands alone. It needs a modifier, either 的 plus a description (我小的时候, when I was little) or a question word (你什么时候来, when are you coming). Contrast it with 时间, the other common word for time. 时间 is measurable duration (时间不够, not enough time); 时候 is an occasion (那时候, back then).
The story behind the character
时
The traditional 時 is 日 (sun) plus 寺 (sound). No clocks back then, so you read the sun to tell the time. That's why 时 has 日 in it. Where the sun sits is what time it is.
候
亻 (person) plus 矦 (sound). It meant to watch for, to wait. A person standing there waiting, that's 候.