保持: (维持; 使不消失或减弱) keep; hold; retain; maintain; preserve 短语和例子保持安静 keep quiet; 保持优势 hold on to a dominant [favorable] position; 保持警惕 maintain vigilance; be on the alert; 保持清洁 keep clean; 保持优良传
呼叫: 1.(呼喊) call out; shout 短语和例子高声呼叫 call out with a loud voice; 他大声呼叫他的妻子。 he called out for his wife.2.[讯] (电台上用呼号叫对方) call; ring; 呼叫表 calling list; 呼叫插塞 calling plug; 呼叫次数 number of calls;