49. --- Does he study very hard at school? --- Yes, he studies _____.
I can ______ the house being untidy, but I hate it if it's not clean.
Unfortunately, the computer system ________ suddenly while they were searching for some information on the Internet.
______with the size of the whole earth, the biggest ocean does not seem big at all.
Alice’s father always brings her a nice gift ________ he returns home from his business trip.
Having walked in the desert for several days, they felt exhausted, but they had to find a pool before the water in the bottle ___________ .