The U.S.A. is ______ country. English is spoken as the first language.
A：an English-spoken
B：a speak English
C：a speaking English
D：an English-speaking
关于蒸发和沸腾，下列说法正确的是（ ）
下列可以调整光线强弱的是（ ）
Now my mom and I _________ watching TV.
