The theory of black holes in space__ (accept) by many serious scientists and astronomers.
is accepted
暂无解析
_______(safe)needstobeimprovedontherailwaysinthatcountry
Our most ________(success)product is based on a very simple idea
Thepresentcrisisbearssome________(similar)totheoilerisisofthe1970s
Thefixedstarwasaplanet.（）
Forthoseinvolved,thescandalhasbeenavery________(pain)experience