Help

[tomwilliamson115 at gmail.com]

I need to write a program that allows the user to enter a sentence then asks them which word they wish to find- and then tell them the position that word was within the sentence. 

E.g. Please help with this code 
Then they enter help it would return that it appears in the 2nd position in the sentence. 

>From what I gather it appears to be a list function but I am struggling to come up with a solution. 

Thanks.