Answer :
The task involves filling in the blanks with either 'if' or 'when'. To determine which word to use, it's helpful to understand the context of each sentence:
If I'm late this evening, don't wait for me.
- Here, 'if' is correct because the sentence is conditional. The speaker is giving a possible scenario (being late) and suggesting an action based on that condition.
When I come back, we can have lunch.
- 'When' is used because it indicates an event that is certain to happen at some point, rather than just a possibility.
I'm going to do some shopping now. If I go, will you come with me?
- 'If' is appropriate here, as it introduces a condition: the speaker is considering the possibility of going shopping and is asking for the listener's company based on this condition.
If you don't want to go out tonight, we can stay at home.
- 'If' is correct here once again, as it indicates a condition. The plan to stay at home depends on the listener's preference.
Do you mind if I close the window?
- 'If' is suitable here, as it asks for permission based on the condition that closing the window might be acceptable.
John is still at school. When he leaves school, he wants to go to university.
- 'When' is used because it refers to a future event expected to happen.
Shall we have a picnic tomorrow if the weather is good?
- 'If' is used here because it introduces a condition that the activity depends on, which is the state of the weather.
We're going to Madrid next week. We haven't got anywhere to stay - we hope to find a hotel when we arrive. I don't know what we'll do if we don't find anywhere.
- 'When we arrive' is certain to happen, so 'when' is used.
- 'If we don't find anywhere' expresses a condition that might or might not occur, thus 'if' is appropriate.
By understanding whether a condition is certain or possible, you can determine whether to use 'if' or 'when' in a sentence.
