压裂液按其物理化学性质不同可分为水基压裂液、油基压裂液、酸基压裂液和()。
A、雾化压裂液
B、泡沫压裂液
C、碱基压裂液
D、盐基压裂液
参考答案:B
If he _____ with us, we _____ finish the task earlier last time. [ ]
A. is; will
B. is; would
C. was; will
D. were; would
心脏为人提的血液循环提供( )
A.场所
B.动力
C.血液
D.原料