EachyearintheUnitedStates,manyblackteenagers_______ofschool,eitherbecausetheycannotkeepuportheyhavetoworktosupporttheirfamily.
A、goout
B、dropout
C、checkout
D、pullout
Theenginehasbrokenandtheboatis______onthewater.
A、flowing
B、floating
C、drifting
D、sailing
I'm______tograduateinthenexthalfoftheyear.
A、owing
B、thanks
C、due
D、because
________somanypeopleintheUnitedStatesbeenoutofworkastoday.
A、Morethaneverbefore
B、Inthepast,therehavenever
C、Neverbeforehave
D、Formerly,thereneverwere
Wemust______thattheexperimentiscontrolledasrigidlyaspossible.
A、assure
B、secure
C、ensure
D、issue