work in this office—No, as a clerk in this office is on vacation, I’mjust ____ here for about a week

Every day Mother sets about her housework ______ she returns from workWhich of the followingis NOT OK? [ ]

I met your uncle on my way to school this morning.—Ah You _____ be joking. He flew to Germany yesterday evening!

you finished your experiment report, Jane— Oh, my God I’ve _____ forgotten all about that

When we entered the room, the light _____ suddenly.