Studies show that people are more ______ to suffer from back problems if they always sit before computer screens for long hours.
On my birthday I got a watch from my uncle, ___ was made in Japan.
I passed by the sports field the other day, __ there was a football match going on then.
__ every mistake you make, you’ll lose half a mark.
--Why don't you try your best to get on the bus?—I tried to , but I could, it started moving.
My study of biology has ___ much of my spare time, ____ it has given me a great deal o enjoyment.