Usage of `also' in a sentence

Which of the following sentences are gramatically correct. In case, a sentence is not correct, then could someone let me know the reason(s):

1) We plan to make project 1 stronger. We have also been working on project 2.
2) We plan to make project 1 stronger. We also have been working on project 2.
3) We plan to make project 1 stronger. We have been also working on project 2.
4) We plan to make project 1 stronger. We have been working also on project2.
5) We plan to make project 1 stronger. We have been working on project 2 also.
6) We plan to make project 1 stronger. Also, we have been working on project 2.

[Tdol]

They're OK, but some are more common than others; 1,3 & 6.

[MikeNewYork]

Originally Posted by Anonymous

Which of the following sentences are gramatically correct. In case, a sentence is not correct, then could someone let me know the reason(s):

1) We plan to make project 1 stronger. We have also been working on project 2.
2) We plan to make project 1 stronger. We also have been working on project 2.
3) We plan to make project 1 stronger. We have been also working on project 2.
4) We plan to make project 1 stronger. We have been working also on project2.
5) We plan to make project 1 stronger. We have been working on project 2 also.
6) We plan to make project 1 stronger. Also, we have been working on project 2.

I'm not sure what "make project 1 stronger" means. Is it really the project that you are strengthening or is the project intended to improve something else?