Common ground

[dina]

Test No. incompl/inter-71 "How to disagree", question 6

I really see no point in continuing this argument because we have no ......... ground.

(a) basic
(b) own
(c) common
(d) similar

Test No. incompl/inter-71 "How to disagree", answer 6

I really see no point in continuing this argument because we have no common ground.

Correct answer: (c) common

Your answer was: incorrect
I really see no point in continuing this argument because we have no similar ground.
_________________________

Dear Alan,

I really see no point in continuing this argument because we have no common ground.

why the answer similar is not suit for that sentence

thanks

[Torsten]

Because common ground is a set phrase, it means that people share the same opinion on a particular question.

TOEIC listening, talks: Describing the advantages of investing in the stock market