We can not figure out quite a number of insects, birds, and animals are dying out.
With their son ______, the old couple lived a hard life.
He must have been working really hard these days. This morning, I even noticed ______ behind his ears.
On almost all the buses in our city, there are seats ______ reserved for disabled and elderly passengers.
We’d better hurry up. The exhibition hall is a bit far from ______ we are now.
The old man lives alone on an island, and his home is not accessible ______ by boat.