Difference between lone, alone and lonely

[Sophie]

I have some exercises with these words.
1. There was only a ... traveller sitting in the waiting room.
a. lone
b. lonesome
c. lonely
d. alone
2. He ... can do the work.
a. alone
b. singly
c. individually
d. all are correct
3. The boy has done the work all by his ...
a. lone
b. lonely
c. lonesome
d. alone
Please help me with these exercises. And I also want to know the uses of each word so that I can gain more experiences.
Thanks a lot.
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On earth there is nothing great but man, in man there is nothing great but mind.

[Lost_Soul]

Hi, Sophie

I can answer your third question: the answer is "lonesome".
There's an idiom all by one's lonesome which means by oneself, which you have to learn.
Take a look at this reference: http://www.answers.com/topic/alone