单选题 Although cats cannot see in complete darkness, their eyes are much more ______ to light than human eyes.

单选题 I am sure that with your remarkable ability and rich experience, the current session you ______ over will be a success.

单选题 The environmental problems are of global importance, and only an international effort would ______ to deal with them.

单选题 In this book the writer describes in great detail how these birds ______ their young.

单选题 ______ his pioneering work in the late 1930s, Earl Hines has been called the father of modern jazz piano.

单选题 If you want to clarify the fact, you need two witnesses to ______ that this is your signature.

单选题 Every year schools all over the country will ______ new students the first week in September.

单选题 Some taxonomists, particularly those working in herbaria and providing an identification service, do need such ______.