In Family-1 医院 is translated as school, whereas it should be hospital.
There is a typo in the notes for Greetings:
你很高兴。 Wǒ[wó] hěn gāo xìng.
Hmm, I don't know. If it's in the notes check if the problem is in the lesson, and report it. If it's not there, tell a course moderator --- make sure it's for Chinese.