Some versus Reason

[Van Khanh]

Please telll me the difference in meaning btw these sentences withsome and certain in:

1. Used for things:

a. For some reason, he will not be able to attend.
b.For certain reasons,he will not be able to attend.

2. Used for people:

c. Some Mr Davis at the door is asking to ask you.
d. A certain Mr Davis at the door is asking to ask you.


Thanks
K

[Mister Micawber]

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For A and C, some = 4. Unknown or unspecified by name: For some reason, some man called.

For B and D, respectively, certain = 6a. Not specified or identified but assumed to be known: He felt that certain breeds did not make good pets. 6b. Named but not known or previously mentioned: a certain Ms. Johnson.

(Courtesy of American Heritage Dictionary)
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Native English teacher at Mister Micawber's

[Pamela]

As far as I know Some Mr Davis can also be substituted for One Mr. Davis

Right, MM?

[Van Khanh]

Dear Sir,

What do 4, 6a, 6b mean?

How about:

For a certain reason, he will not be able to attend.

Thanks

[Mister Micawber]

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Yes, Pamela-- one Mr Davis, some Mr Davis, a Mr Davis, a certain Mr Davis: these all refer to a man who has given his name, but with whom the butler is unfamiliar.

The numbers are the numbers of the definitions in that dictionary, Van. There are multiple meanings for each word.

For a certain reason indicates that the speaker knows the reason but is for some reason unwilling to share that knowledge.
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_________________
Native English teacher at Mister Micawber's

[Yankee]

[Van Khanh]

Dear Sir,

Please read:

a.For some reasons, he will not be able to attend.
b.For a some reason, he will not be able to attend.
c.For certain reason, he will not be able to attend.
d. A some Mr Davis at the door is asking to ask you.
e.Certain Mr Davis at the door is asking to ask you.
f.Some Mr Davis at the door are asking to ask you.
g. Certain Mr Davis at the door are asking to ask you.

Please lisht me all right sentences and tell me their different meanings. (That means the sentence(s) you don't list is/are wrong).

Thanks
K

[Yankee]

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The sentences are all incorrect, in my opinion.
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