Thisrobotissupposedt的精选

问题详情：Thisrobotissupposedtosavealotoflabor,butitremainsaproblemifit______.A.isB.savesC.doesD.has【回答】C【解析】do(es)是代动词，用来代替上文savealotoflabor。知识点：动词时态题型：选择题...