#answers input {display: block;}

这将使每个输入都在自己的行中。
如果您希望将每个输入的标签放在一行中，您应该做一些类似于

this will make every input in its own line. If you wish to have every input with its label together in a line you should do something like

<form id="answers">
    <label>blue <input id="0" type="radio"></label>
    <label>red <input id="1" type="radio"></label>
    <label>pink <input id="2" type="radio"></label>
    <input type="submit">
</form>

css：
#answers label {display：block;}

css: #answers label {display: block;}

http://jsfiddle.net/barakedry/y6p54vzg/