They _______ some books from the library last week.
They learned it all by themselves. That is to say nobody told them ________ .
--- Are there ___________ students in your school? --- Yes, _____________ the students is about 2000.
___________ it snows, ____________ the children feel.
Luo Yang devoted all his life _________for China Nation Aviation(中国航天).
______ the age of 89, he passed away ______ a cold winter morning.