Pleasewriteareport________theabovesubjectsaretobecovered.
A、whichB
in which the above subjects are to be covered 是 report 的定语从句。 which 指代先行词report ， in 用于与 report 搭配。
WhichofthefollowingcountryisnotamemberofOECD?
Scientistsdoubtwhetherit’s________toregulateone’sbiologicalclockbydrinking.
Bythemiddleofthe21stcentury,thevastmajorityoftheworld’spopulationwillbelivingincities_______inthecountry.
He found _______ difficult to study maths.
Touristexpenditureshavedifferenteffectsonadestinationeconomy:salesbyfoodvendorstorestaurantsare_______effect;whiletaxifaresandairlineticketsalesare_______effect.
