I tried phoning her office, but I couldn't __________.
______ the terrible pollution, so many beautiful fish are fast disappearing in the river.
All of us found ______ difficult to work out the maths problem.
Doyouhappentoknow________?
Let Tom play with your toys as well, Clare—you must learn to_______.
Johnaskedme_______tovisithisuncle’sfarmwithhim.