Validation - Word Drop

People often type dates of birth in different ways, so the data becomes ______ and is hard to compare or fix. Validation also stops impossible values, such as a ______ age, which is less than zero.

Data validation sets up ______ that check data as it is entered, and shows an ______ explaining the problem when an entry breaks them. To add a rule, select the cells, open the ______ menu and choose Data validation, then save it.

A list rule turns a cell into a ______ menu, so users pick a set option instead of typing. A text rule can check that an entry contains, does not contain or exactly matches a set word, or that it is a valid ______ with an @ symbol. A number rule can allow only ages ______ 0 and 120, or numbers above a set limit. A date rule can insist that a check-in happens ______ today.

When invalid data is typed in, you can show a warning, which allows the data but marks it as invalid, or you can ______ the input so it cannot be entered at all. A validated cell may look no different, but a drop-down shows a small ______. On a hotel booking form, a number rule can limit the number of guests, a list rule can offer set room types and a rule can check that the stay begins on a future ______.