1.Females lay their eggs during the spring and summer months on the underside of milkweed plants then die soon after.
이 문장에서, then 앞에 and가 와서 and then 하고 동사가 다시 나와야 하는거 아닐까요?
then은 접속사가 아니니까 동사가 뒤따라 오지 못할 것 같은데
then은 접속부사 아닌가요??
2. After spending another two weeks as pupae, they become adults, and it appears that the adult Monarchs feed on a variety of nectar plants, at which time their characteristic coloration also seems to appear.
at which 뒤에 나오는 time은 왜 쓰인 걸까요?
at which time이 another two weeks에 걸리는거 맞죠?