I think _______ a foreign language is not easy. You should _______ it often.

I believe your dream will come true one day if you keep on __________ hardfrom now on.

The teacher advised the parents to talk with their son _______.

You’ll find taxies waiting at the bus station ________ you can hire to reach your hotel.

The six­year­old girl infected with the H7N9 bird flu is in a ________ condition after receiving treatment.