对于给定的英文文章，将所有句子中的主语提取出来，并在每个主语后面加上冒号。
The quick brown fox jumps over the lazy dog. The little kitten plays with the ball of yarn. The bird is chirping early in the morning.
The quick brown fox: jumps over the lazy dog.
The little kitten: plays with the ball of yarn.
The bird: is chirping early in the morning.