_____relatively rare ,serious confrontations between students do happen

A．if only

B．though

C．whereas

D．as if

[名词解释] 偶见种（rare species）

[单选题]F．or serious study, an anthropologist ______.A．) must not study his own cultureB．) is not supposed to have a prejudice against any societyC．) should focus on those societies which are historically related to each otherD．) is obliged to work only on t

[名词解释] 稀有元素(rare element)

[试题]______(affect)with a serious disease，Van Wendel was no longer able to speak clearly and he knew there was no hope of recovery.

[单选题]D．uring the war there was a serious lack of food. It was not unusual that even the wealthy families had to bread for days.A． eat up B. give away C. do without D. deal with

[单选题]Thosegiftsofrarebooksthatweregiventousweredeeply_______.A)appreciatedB)approvedC)appealedD)applied

[单选题]The demand for products from monopolistic competitors is relatively elastic

[单选题]ThatwassoseriousamatterthatIhadnochoicebut________thepolice.A．)calledinB)callinginC．)callinD)tocallin

[单选题][A] small[B] few[C] rare[D] scarce

[单选题]［A］ scarce ［B］ little ［C］ rare ［D］ poor