30.Some children want to challenge themselves by learning a language different from____spoken by their parents at home.
David couldn't tell __________ from far away whether the green traffic light meant going straight or turning left.
-Are you a volunteer now? -No, but I __________. I worked for the City Sports Meeting last year.
He used to __________cards, but now he is used to __________ a walk after supper.
Whenever my parents talk with me, they always __________ great importance to how important and necessary it is for us young people __________ ourselves both in work and in life.
I wondered what difficulty he had __________ the plan?