⇒ I think I can speak for everyone here when I express my sincere apologies.我想我能够代表这里的所有人表示由衷的歉意。 (Wǒ xiǎng wǒ nénggòu dàibiǎo zhèlǐ de suǒyǒurén biǎoshì yóuzhōng de qiànyì.)
it speaks for itself这(這)不言而喻 (zhè bù yán ér yù)
speak for yourself! (inf) 谈(談)你自己的意见(見)！ (Tán nǐ zìjǐ de yìjiàn!)
that picture is already spoken for (= reserved) 那幅画(畫)已经(經)有人要了 (nà fú huà yǐjīng yǒu rén yào le)