This line doesn't count

[LewisJian]

When we play single ( game of badminton), this line (the line on the outside) doesn't count.

Is it correct to say "this line doesn't count?" Could I also say "this line is useless" or "don't bother about this line?" If not, how should I say it right? Thanks.

 

[emsr2d2]

When we play singles badminton, ( game of badminton), this line (the line on the outside) doesn't count.

Is it correct to say "This line doesn't count?" Could I also say "This line is useless" or "Don't bother about this line"? If not, how should I say it? right?
Thanks. Unnecessary. Thank us after we help you, by adding the "Thanks" icon to any response you find useful.

None of them are correct. Which line are you talking about? In think you need to learn the term "tramlines". There are tramlines on both sides and at the back of the court. When serving in singles, the tramlines on both sides and at the back are out. In the rest of the rally, in singles, the back tramlines are in but the side tramlines are out. The playable court, after the serve, is long and thin. Anything that lands beyond the baseline, or inside/outside the side tramlines, is out.