the role of the adverb is to modify the verb in a clause or sentence, typically providing information about the manner, place, time, or degree in which the action was done. The adverb ‘when’ can be used to ask questions about the time of occurrence of an event or the time of its commencement.
when used as an adverb, the word ‘when’ always appears at the beginning of the sentence in a question form. The word also has a direct relationship with the verb that appears immediately after ‘when’.
1. When did the movie start?
2. When will the school holiday end?
3. When did you decide to apply to that college?
when used to answer these types of questions, the adverb ‘when’ typically precedes a time-related noun or verb, such as ‘yesterday’, ‘tomorrow’, ‘last week’, etc. It is important to note that, when asking such questions, the word ‘when’ should not be followed by any form of ‘to be’ verb (such as ‘was’ or ‘will be’). This would make the sentence a statement instead of a question.'
when used as a conjunction, 'when' joins two clauses to indicate that one event must occur before the other.
'when' can be used as conjunction to refer to a specific time when an event occurred, describe simultaneous events, indicate cause or reason, or describe a condition.
1. I will begin working on the project when I get the materials.
2. He fell asleep when the movie ended.
3. We’ll organize the party when everyone arrives.
Avoid Using 'When' with the Future Perfect. It's uncommon to use 'when' with the future perfect tense. Instead, use the present simple or present perfect. 'When' is often used for actions that happen at a specific moment, while 'while' is used for actions that occur over a period of time.