太阳及其行星统称为太阳系. The sun and its planets are called the.

We should teenagers to their own clothes.

Zhang Yimou is a and the films have won many awards.

让我们写一封信给西格蒙德·弗兰德先生。

Many young people and want to become like them.

I him learn English hard.

→(adj. ) 有挑战性的