Our sales_____ for months, so we are now in great financial difficulties. A: had been dropping B: have been dropping C: have been dropped D: are dropping

某LTI系统，其输入为f(t)，输出y(t)为函数1/a·s(x-a/a)f(x-2)在x为[-∞，∞]区间的积分，其中a为常数，且已知s(t)S(jw)，则系统的频率响应 H(jw)为 A: e-j2wS(-jaw)·|a|/a B: S(-jaw)·|a|/a C: ej2wS(-jaw) D: ej2wS(-jaw)·|a|/a

Nerves go through the ( ). A: jaw bone B: pulp C: gums

中国大学MOOC: Nowadays, we often associate civil engineering with the worlds most jaw-dropping structures.

Elision means the dropping of a sound or sounds. ( )

Kuwait is famous for its _________ resources. A: petroleum B: ja C: fame D: jaw

Kuwait is famous for its _________ resources. A: petroleum B: .jar C: fame D: jaw

I've lost one of my gloves. I ___it somewhere in this room. A: must drop B: must have droppped C: must be dropping D: must have been dropping

Emily Dickinson is good at the charm of something but dropping the thing itself. ( )

The dropping of the two atom bombs by America forced _____ to surrender unconditionally.