在座zài zuò

在聚会、宴会等的座位上；在场：（宝玉）只略坐了一坐，便走开各处闲耍…（贾珍等）纵一时不见他～，只道在里边去了，故也不问。(十九·404)当日敢是宝公也～，见其娇且闻其香否？不然，何体贴至此。(七八·1950)

在座

be present (at a meeting,banquet,etc)
我提议为今晚～的各位朋友的健康干杯！ I propose a toast to the health of all our friends present here tonight!/希望～的朋友们多提意见。We hope you friends here will not hesitate to give your opinions and criticisms./～的还有：also present are: