问题
选择题
---How can you keep slim as a mother of two sons?
---I _______ in the gym for years.
A．have worked out
B．have been working out
C．have worked on
D．have been working on
答案
答案：B
句意：作为两个儿子的母亲你怎么能保持这么苗条？我这些年一直在体育馆锻炼。Work out锻炼，work on从事；. have been working out现在完成进行时，表示从过去一直到现在进行的动作，有可能还会进行下去。所以选B。