Since there was no witness to the crime, it will be difficult to solve.
It can be a verb or a noun. It depends on how you use it. If someone says "I will murder him," than it's a verb, but if I say "Did we just wittnes a murder," than the verb would be wittnes and murder would be a noun.
i do not know how to use embalming in a sentence. (there is the sentence)
So- you are asking when to use 'when' in a sentence. When you are asking how to use when in a question, you are already using when in a sentence, because a question actually is a sentence. I like to use when in a sentence whenever I like.
How do you use sedition in a sentence
use contingency in a sentence?
use adainty as sentence
Can you use abstemious in a sentence?
use inmates in sentence
use figureatively in a sentence
Use it in a big sentence.
can i use polymer in a sentence
.. how can use scrum in a sentence