article -'a'

English as a Second Language English Vocabulary, Grammar and Idioms
1
  1. He has (a) good knowledge of English grammar.
  2. Please take (a) good care of him.
  3. Is your car giving (a) good mileage?
  4. Do you get (a) good mileage from your car?
    In all these sentences ‘a’ is optional or compulsory?
    Please comment.
    Thanks.
2

The “a” is not correct in any sentence except for #1, in which it is optional, though I would lean towards including it.

3 
 Hello, Luschen:

Thanks to your reply, I have learned a new thing, i.e.:

  1. The phrase lean to/towards take an -ing form of the verb, doesn’t it?

  2. Can the phrase lean to/towards be synonymous with the phrases in bold below and can I use the following phrases in place of it?

a) ... though I would [b] be prone to include[/b] it.

b) ... I would [b]be inclined to include[/b] it.

 Many thanks..
4

Luschen, I have seen my American friends always use ‘toward’ not 'towards. You are an exception now.

5

I did some research concerning the first sentence and came to the conclusion that “a” is obligatory in this case.

6

Thanks for your reply, Foreigner.

7 
     Hello, DEAR TEACHER:

When I wrote the phrase thanks to I meant “owing to, due to”. Am I wrong?

 Thanks.
8

No Foreigner, you weren’t wrong in your choice of preposition, but your punctuation was not right and so the meaning became confused:

Thanks to your reply I have learned something new.
Thanks for your reply. I have learned something new.

9

So the comma in the first sentence is not needed. Thanks.)

10

On the other hand, if you meant as I took it, a semi colon would be more suitable than a comma, I think. Thanks for your reply; I have learned something new.
What do you say?

11

I say a full stop or a comma would be better.
A semi-colon rather than either of those serves no purpose there.