1. Make sure all windows are closed.
2. Make certain all windows are closed.
3. Be certain all windows are closed.
4. Be certain that all windows are closed.
5. Be sure to come here in time.
6. Be certain to come here in time.
7 Make sure you don't smoke in this room.
8. Make certain you don't smoke in this room.
9. Make sure not to smoke in this room.
10. Make certain not to smoke in this room.
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Can we use all the expressions?
Are 'sure' and 'certain' interchangable in this case?
Yes.
Yes, all of the expressions listed can be used to convey the same intention, which is to emphasize the importance of ensuring that all windows are closed or that smoking is not allowed in a specific room.
As for the interchangeability of "sure" and "certain," they can be used interchangeably in most contexts. Both words convey a high level of confidence or conviction. However, it's worth noting that "certain" tends to sound more formal or formal-sounding, while "sure" is more commonly used in everyday conversations. So while both words can be used interchangeably, the choice between "sure" and "certain" may depend on the desired tone or level of formality in a given situation.