．— Have you ever visited the Opera House?
—Yes．When I was in Sydney, I ______ it twice．
A．have visited B．visited C．had visited D．would visit
Oh, much smoke here ! Somebody _____ the window, please.
A. opens B. open C. shall open D. will open
She looked up and nodded for me ______..
A. to come in B. coming in C. came in D. come in
Catherine bought a postcard of the place she was visiting, addressed _______ to _______ and then posted it at the nearby post office.
A. it; her B. it; herself C. herself; her D. herself; herself
. I love hobbies ______ you can see hard work and perseverance turn into positive results.
A. which B. that C. when D. where
So far no life has been found outside the earth, but while some scientists are actively searching for living things in outer space, others firmly believe there ____ .
A. mustn’t be B. may not be C. can’t be D. won’t be
