Since we have a focused subject， we should not talk ________.
A. at once B. at hand C. at intervals D. at random
译文：既然我们已经有了命题，我们就不应漫无边际地交谈。此题考查对固定短语的掌握情况。at once立刻;at hand在附近，在手头，即将发生;at intervals间或，不时;at random随便，任意。
苏公网安备 32050602011079号