My friend Tom is a schoolboy. Everyone likes him very much because he is kind. He likes to help people. He is a smart boy and he can play many musical instruments(乐器). After school, when he is with his friends, he often plays musical instruments for them. On weekends, he is free and he always goes to the old people's home. He plays the violin and the guitar to make them happy. He thinks it's interesting and fun.

    Today is February 28th. It's Tom's birthday. He has a big and interesting party at home. Many friends come to his party. Tom's mother cooks a lot of food for them. Everyone gives a beautiful gift to him. Sally gives him an English dictionary because Tom also likes English. Bob gives Tom a guitar because he likes playing the guitar very much. At the party, Tom plays the guitar and he also plays the piano. We sing many songs and play some interesting games. We have a good time today.

①大众传媒日益成为文化传播的主要手段

②传媒的商业性给文化生活带来可喜变化

③大众传媒促进了先进文化的传播

④科学技术进步会影响文化发展

“好雨知时节，当春乃发生。随风潜入夜，润物细无声。”杜甫这首诗表现了诗人的情绪是（    ）