While it is always important to ask clear and unambiguous questions regardless of the method that you use, it is especially important to avoid confusion when conducting surveys. why?

A survey is a group of questions aimed at getting information on the respondents. Because a survey relies on people self-reporting their activities, behaviours or ideas, which you would have to trust (i. e. there is no information that comes from your observations), you have to be particularly careful with misunderstandings. If a person does not understand your question, or does not do so in the specific way that is necessary for your research, you could end up measuring a completely different variable and your research would lack internal validity.