__________ the help of modern technology， scientists got a photo of a black hole．（ ）
A．AtB．InC．OnD．With
Write down these useful sentences，___________you'll forget them.（ ）
A．andB．orC．butD．so
Bill is running so fast!I _________believe my eyes.（ ）
A．needn'tB．shouldn'tC．mustn'tD．can't
There __________two people waiting for you outside now.（ ）
A．isB．areC．wasD．were
My cousin keeps two pets.One is a lovely cat and ___________ is a beautiful bird.（ ）
A．otherB．othersC．the otherD．another
We used to buy things in the ____________ but now we usually do it online.（ ）
A．shopB．museumC．bankD．library