14KiB, 330x152, images.png View SameGoogleiqdbSauceNAO Anonymous Sun 20 Jun 02:54:32 2021 No.13299280 ViewReplyOriginalReport Quoted By: >>13299295 >>13299333 >>13299441 >>13299577 Sorry for brainlet question but it seems my memory has deceived me. When is it legal to "cancel"/contract a partial derivative? Like this red strike is not allowed, right?