Our attitudes towards work-life balance have changed significantly _______ .
A. before we started working from home
B. after we had started working from home
C. since we started working from home
D. until we start working from home
Last night, my husband _______ me up when I was having a terrible nightmare.
Tim must be very tired because he _______ playing the violin for hours!
This is the first time I _______ such an impressive art exhibition.
Peter was entering the construction site when he ________ a dead body on the floor.