There ______ some chopsticks on the table.A、areB、isC、haveD、was

The experiment involves _____ on some mice.

Some well-known scientists believe that there is not enough oxygen on Mars to ______ human

It is possible to escape through the windows______.A．if there are some bushes on the groun

There is some _________whether he will come to th

Some well-known scientists believe that there is not enough oxygen on Mars to ______ human

There ________ a book and some magazines on the desk.A.isB.beC.haveD.has